diff --git a/src/Checker/OrderPaymentEditionChecker.php b/src/Checker/OrderPaymentEditionChecker.php
new file mode 100644
index 0000000..e964ece
--- /dev/null
+++ b/src/Checker/OrderPaymentEditionChecker.php
@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Setono\SyliusOrderEditPlugin\Checker;
+
+use Sylius\Component\Core\OrderPaymentStates;
+use Sylius\Component\Order\Model\OrderInterface;
+use Symfony\Component\HttpFoundation\RequestStack;
+use Webmozart\Assert\Assert;
+
+final class OrderPaymentEditionChecker implements OrderPaymentEditionCheckerInterface
+{
+    public function __construct(private readonly RequestStack $requestStack)
+    {
+    }
+
+    public function shouldOrderPaymentBeEdited(OrderInterface $order): bool
+    {
+        Assert::isInstanceOf($order, \Sylius\Component\Core\Model\OrderInterface::class);
+
+        $request = $this->requestStack->getCurrentRequest();
+        if (null === $request) {
+            return true;
+        }
+
+        if ('setono_sylius_order_edit_admin_update' !== $request->attributes->get('_route')) {
+            return true;
+        }
+
+        return $order->getPaymentState() === OrderPaymentStates::STATE_AWAITING_PAYMENT;
+    }
+}
diff --git a/src/Checker/OrderPaymentEditionCheckerInterface.php b/src/Checker/OrderPaymentEditionCheckerInterface.php
new file mode 100644
index 0000000..3d881aa
--- /dev/null
+++ b/src/Checker/OrderPaymentEditionCheckerInterface.php
@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Setono\SyliusOrderEditPlugin\Checker;
+
+use Sylius\Component\Order\Model\OrderInterface;
+
+interface OrderPaymentEditionCheckerInterface
+{
+    public function shouldOrderPaymentBeEdited(OrderInterface $order): bool;
+}
diff --git a/src/OrderProcessing/OrderPaymentProcessor.php b/src/OrderProcessing/OrderPaymentProcessor.php
index 5a7aec4..2a6df74 100644
--- a/src/OrderProcessing/OrderPaymentProcessor.php
+++ b/src/OrderProcessing/OrderPaymentProcessor.php
@@ -4,26 +4,21 @@
 
 namespace Setono\SyliusOrderEditPlugin\OrderProcessing;
 
+use Setono\SyliusOrderEditPlugin\Checker\OrderPaymentEditionCheckerInterface;
 use Sylius\Component\Order\Model\OrderInterface;
 use Sylius\Component\Order\Processor\OrderProcessorInterface;
-use Symfony\Component\HttpFoundation\RequestStack;
 
 final class OrderPaymentProcessor implements OrderProcessorInterface
 {
     public function __construct(
         private readonly OrderProcessorInterface $decorated,
-        private readonly RequestStack $requestStack,
+        private readonly OrderPaymentEditionCheckerInterface $orderPaymentEditionChecker,
     ) {
     }
 
     public function process(OrderInterface $order): void
     {
-        /** @var mixed $route */
-        $route = $this->requestStack->getCurrentRequest()?->attributes->get('_route');
-
-        // This disables the \Sylius\Component\Core\OrderProcessing\OrderPaymentProcessor if the route is 'setono_sylius_order_edit_admin_update'
-        // which means we are editing the order in the admin panel
-        if ('setono_sylius_order_edit_admin_update' === $route) {
+        if (!$this->orderPaymentEditionChecker->shouldOrderPaymentBeEdited($order)) {
             return;
         }
 
diff --git a/src/Resources/config/services/order_processing.xml b/src/Resources/config/services/order_processing.xml
index 9c8a21d..05bc6eb 100644
--- a/src/Resources/config/services/order_processing.xml
+++ b/src/Resources/config/services/order_processing.xml
@@ -2,11 +2,29 @@
 <container xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://symfony.com/schema/dic/services"
            xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
     <services>
-        <service id="setono_sylius_order_edit.order_processing.order_payment_processor"
-                 class="Setono\SyliusOrderEditPlugin\OrderProcessing\OrderPaymentProcessor"
-                 decorates="sylius.order_processing.order_payment_processor.checkout" decoration-priority="64">
+        <service
+            id="setono_sylius_order_edit.order_processing.order_payment_processor"
+            class="Setono\SyliusOrderEditPlugin\OrderProcessing\OrderPaymentProcessor"
+            decorates="sylius.order_processing.order_payment_processor.checkout" decoration-priority="64"
+        >
             <argument type="service" id="setono_sylius_order_edit.order_processing.order_payment_processor.inner"/>
-            <argument type="service" id="request_stack"/>
+            <argument type="service" id="setono_sylius_order_edit.checker.order_payment_edition"/>
+        </service>
+
+        <service
+            id="setono_sylius_order_edit.order_processing.order_payment_processor.after_checkout"
+            class="Setono\SyliusOrderEditPlugin\OrderProcessing\OrderPaymentProcessor"
+            decorates="sylius.order_processing.order_payment_processor.after_checkout" decoration-priority="64"
+        >
+            <argument type="service" id="setono_sylius_order_edit.order_processing.order_payment_processor.after_checkout.inner"/>
+            <argument type="service" id="setono_sylius_order_edit.checker.order_payment_edition"/>
+        </service>
+
+        <service
+            id="setono_sylius_order_edit.checker.order_payment_edition"
+            class="Setono\SyliusOrderEditPlugin\Checker\OrderPaymentEditionChecker"
+        >
+            <argument type="service" id="request_stack" />
         </service>
 
         <service
diff --git a/tests/Functional/OrderUpdateTest.php b/tests/Functional/OrderUpdateTest.php
index 5507070..91d60d4 100644
--- a/tests/Functional/OrderUpdateTest.php
+++ b/tests/Functional/OrderUpdateTest.php
@@ -8,6 +8,7 @@
 use Setono\SyliusOrderEditPlugin\Entity\EditableOrderInterface;
 use Setono\SyliusOrderEditPlugin\Model\AdjustmentTypes;
 use Setono\SyliusOrderEditPlugin\Tests\Application\Entity\Order;
+use SM\Factory\FactoryInterface;
 use Sylius\Bundle\ApiBundle\Command\Cart\AddItemToCart;
 use Sylius\Bundle\ApiBundle\Command\Cart\PickupCart;
 use Sylius\Bundle\ApiBundle\Command\Checkout\ChoosePaymentMethod;
@@ -17,9 +18,11 @@
 use Sylius\Component\Core\Model\Address;
 use Sylius\Component\Core\Model\AdjustmentInterface;
 use Sylius\Component\Core\Model\OrderInterface;
+use Sylius\Component\Core\Model\PaymentInterface;
 use Sylius\Component\Core\Model\ProductVariantInterface;
 use Sylius\Component\Core\Repository\OrderRepositoryInterface;
 use Sylius\Component\Core\Repository\ProductVariantRepositoryInterface;
+use Sylius\Component\Payment\PaymentTransitions;
 use Symfony\Bundle\FrameworkBundle\KernelBrowser;
 use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;
 use Symfony\Component\Messenger\MessageBusInterface;
@@ -95,8 +98,28 @@ public function testItAllowsToAddDiscountsForTheWholeOrder(): void
 
         self::assertResponseStatusCodeSame(302);
 
+        /** @var OrderInterface $order */
+        $order = $this->getOrderRepository()->findOneBy(['tokenValue' => 'TOKEN']);
+        self::assertSame($initialOrderTotalWithoutTaxes - 100, $this->getResultTotal($order));
+        self::assertCount(1, $order->getPayments()->toArray());
+    }
+
+    public function testItDoesNotChangePaymentsForAlreadyPaidOrders(): void
+    {
+        $order = $this->placeOrderProgrammatically(quantity: 5, paid: true);
+        $initialOrderTotalWithoutTaxes = $this->getInitialTotal($order);
+        $initialPaymentTotal = $order->getPayments()->first()->getAmount();
+
+        $this->loginAsAdmin();
+        $this->addDiscountsToOrder($order->getId(), [1]);
+
+        self::assertResponseStatusCodeSame(302);
+
+        /** @var OrderInterface $order */
         $order = $this->getOrderRepository()->findOneBy(['tokenValue' => 'TOKEN']);
         self::assertSame($initialOrderTotalWithoutTaxes - 100, $this->getResultTotal($order));
+        self::assertCount(1, $order->getPayments()->toArray());
+        self::assertSame($initialPaymentTotal, $order->getPayments()->first()->getAmount());
     }
 
     public function testItAllowsToAddAndRemoveDiscountsForTheWholeOrderMultipleTimes(): void
@@ -209,6 +232,7 @@ public function testItAllowsToAddStoreNotes(): void
     private function placeOrderProgrammatically(
         string $variantCode = '000F_office_grey_jeans-variant-0',
         int $quantity = 1,
+        bool $paid = false,
     ): EditableOrderInterface {
         /** @var MessageBusInterface $commandBus */
         $commandBus = self::getContainer()->get('sylius.command_bus');
@@ -252,6 +276,15 @@ private function placeOrderProgrammatically(
         $completeOrder->setOrderTokenValue('TOKEN');
         $commandBus->dispatch($completeOrder);
 
+        if ($paid) {
+            /** @var FactoryInterface $stateMachineFactory */
+            $stateMachineFactory = self::getContainer()->get('sm.factory');
+            /** @var PaymentInterface $payment */
+            $payment = $order->getPayments()->first();
+            $stateMachineFactory->get($payment, PaymentTransitions::GRAPH)->apply(PaymentTransitions::TRANSITION_COMPLETE);
+            self::getEntityManager()->flush();
+        }
+
         return $this->getOrderRepository()->findOneBy(['tokenValue' => 'TOKEN']);
     }
 
diff --git a/tests/Unit/Checker/OrderPaymentEditionCheckerTest.php b/tests/Unit/Checker/OrderPaymentEditionCheckerTest.php
new file mode 100644
index 0000000..6264be9
--- /dev/null
+++ b/tests/Unit/Checker/OrderPaymentEditionCheckerTest.php
@@ -0,0 +1,71 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Setono\SyliusOrderEditPlugin\Tests\Unit\Checker;
+
+use PHPUnit\Framework\TestCase;
+use Prophecy\PhpUnit\ProphecyTrait;
+use Setono\SyliusOrderEditPlugin\Checker\OrderPaymentEditionChecker;
+use Sylius\Component\Core\Model\OrderInterface;
+use Sylius\Component\Core\OrderPaymentStates;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\RequestStack;
+
+final class OrderPaymentEditionCheckerTest extends TestCase
+{
+    use ProphecyTrait;
+
+    public function testItSaysOrderPaymentsShouldNotBeEditedIfTheRouteIsOrderEditAndThePaymentIsAlreadyProcessed(): void
+    {
+        $requestStack = $this->prophesize(RequestStack::class);
+        $request = new Request([], [], ['_route' => 'setono_sylius_order_edit_admin_update']);
+        $requestStack->getCurrentRequest()->willReturn($request);
+
+        $checker = new OrderPaymentEditionChecker($requestStack->reveal());
+
+        $order = $this->prophesize(OrderInterface::class);
+        $order->getPaymentState()->willReturn(OrderPaymentStates::STATE_AUTHORIZED);
+
+        self::assertFalse($checker->shouldOrderPaymentBeEdited($order->reveal()));
+    }
+
+    public function testItSaysOrderPaymentShouldBeEditedItTheRouteIsOrderEditButOrderIsAwaitingPayment(): void
+    {
+        $requestStack = $this->prophesize(RequestStack::class);
+        $request = new Request([], [], ['_route' => 'setono_sylius_order_edit_admin_update']);
+        $requestStack->getCurrentRequest()->willReturn($request);
+
+        $checker = new OrderPaymentEditionChecker($requestStack->reveal());
+
+        $order = $this->prophesize(OrderInterface::class);
+        $order->getPaymentState()->willReturn(OrderPaymentStates::STATE_AWAITING_PAYMENT);
+
+        self::assertTrue($checker->shouldOrderPaymentBeEdited($order->reveal()));
+    }
+
+    public function testItSaysOrderPaymentShouldBeEditedIfItsNotOrderEditRoute(): void
+    {
+        $requestStack = $this->prophesize(RequestStack::class);
+        $request = new Request([], [], ['_route' => 'sylius_admin_order_any_other_route']);
+        $requestStack->getCurrentRequest()->willReturn($request);
+
+        $checker = new OrderPaymentEditionChecker($requestStack->reveal());
+
+        $order = $this->prophesize(OrderInterface::class);
+
+        self::assertTrue($checker->shouldOrderPaymentBeEdited($order->reveal()));
+    }
+
+    public function testItSaysOrderPaymentShouldBeEditedIfThereIsNoCurrentRequest(): void
+    {
+        $requestStack = $this->prophesize(RequestStack::class);
+        $requestStack->getCurrentRequest()->willReturn(null);
+
+        $checker = new OrderPaymentEditionChecker($requestStack->reveal());
+
+        $order = $this->prophesize(OrderInterface::class);
+
+        self::assertTrue($checker->shouldOrderPaymentBeEdited($order->reveal()));
+    }
+}
diff --git a/tests/Unit/OrderProcessing/OrderPaymentProcessorTest.php b/tests/Unit/OrderProcessing/OrderPaymentProcessorTest.php
index fd74b88..ee73c4d 100644
--- a/tests/Unit/OrderProcessing/OrderPaymentProcessorTest.php
+++ b/tests/Unit/OrderProcessing/OrderPaymentProcessorTest.php
@@ -6,45 +6,42 @@
 
 use PHPUnit\Framework\TestCase;
 use Prophecy\PhpUnit\ProphecyTrait;
+use Setono\SyliusOrderEditPlugin\Checker\OrderPaymentEditionCheckerInterface;
 use Setono\SyliusOrderEditPlugin\OrderProcessing\OrderPaymentProcessor;
-use Sylius\Component\Core\Model\OrderInterface;
+use Sylius\Component\Core\Model\Order;
 use Sylius\Component\Order\Processor\OrderProcessorInterface;
-use Symfony\Component\HttpFoundation\Request;
-use Symfony\Component\HttpFoundation\RequestStack;
 
 final class OrderPaymentProcessorTest extends TestCase
 {
     use ProphecyTrait;
 
-    public function testItDoesNotAllowToProcessOrderIfItsEdited(): void
+    public function testItDoesNotAllowToProcessOrderIfItShouldNotBeEdited(): void
     {
         $orderProcessor = $this->prophesize(OrderProcessorInterface::class);
-        $requestStack = $this->prophesize(RequestStack::class);
-        $request = new Request([], [], ['_route' => 'setono_sylius_order_edit_admin_update']);
-        $requestStack->getCurrentRequest()->willReturn($request);
+        $orderPaymentEditionChecker = $this->prophesize(OrderPaymentEditionCheckerInterface::class);
 
-        $processor = new OrderPaymentProcessor($orderProcessor->reveal(), $requestStack->reveal());
+        $processor = new OrderPaymentProcessor($orderProcessor->reveal(), $orderPaymentEditionChecker->reveal());
 
-        $order = $this->prophesize(OrderInterface::class);
+        $order = new Order();
 
+        $orderPaymentEditionChecker->shouldOrderPaymentBeEdited($order)->willReturn(false);
         $orderProcessor->process($order)->shouldNotBeCalled();
 
-        $processor->process($order->reveal());
+        $processor->process($order);
     }
 
-    public function testItDoesNothingIfItsDifferentRoute(): void
+    public function testItDoesNothingIfItShouldBeEdited(): void
     {
         $orderProcessor = $this->prophesize(OrderProcessorInterface::class);
-        $requestStack = $this->prophesize(RequestStack::class);
-        $request = new Request([], [], ['_route' => 'some_other_route']);
-        $requestStack->getCurrentRequest()->willReturn($request);
+        $orderPaymentEditionChecker = $this->prophesize(OrderPaymentEditionCheckerInterface::class);
 
-        $processor = new OrderPaymentProcessor($orderProcessor->reveal(), $requestStack->reveal());
+        $processor = new OrderPaymentProcessor($orderProcessor->reveal(), $orderPaymentEditionChecker->reveal());
 
-        $order = $this->prophesize(OrderInterface::class);
+        $order = new Order();
 
+        $orderPaymentEditionChecker->shouldOrderPaymentBeEdited($order)->willReturn(true);
         $orderProcessor->process($order)->shouldBeCalled();
 
-        $processor->process($order->reveal());
+        $processor->process($order);
     }
 }