diff --git a/service-api/app/src/App/src/Service/Lpa/ResolveActor/SiriusHasActorTrait.php b/service-api/app/src/App/src/Service/Lpa/ResolveActor/SiriusHasActorTrait.php
index a56960e4e8..32bcb85783 100644
--- a/service-api/app/src/App/src/Service/Lpa/ResolveActor/SiriusHasActorTrait.php
+++ b/service-api/app/src/App/src/Service/Lpa/ResolveActor/SiriusHasActorTrait.php
@@ -29,8 +29,13 @@ public function hasActor(string $uid): ?LpaActor
 
     private function isADonor(string $uid): ?LpaActor
     {
-        foreach ($this->getDonor()['linked'] as $value) {
-            if ((string) $value['id'] === $uid || $value['uId'] === $uid) {
+        $linkedDonors = $this->getDonor()->linked ?? $this->getDonor()['linked'];
+
+        foreach ($linkedDonors as $linkedDonor) {
+            $linkedDonorId  = $linkedDonor->id ?? $linkedDonor['id'];
+            $linkedDonorUid = $linkedDonor->uId ?? $linkedDonor['uId'];
+
+            if ((string) $linkedDonorId === $uid || $linkedDonorUid === $uid) {
                 return new LpaActor($this->getDonor(), ActorType::DONOR);
             }
         }
diff --git a/service-api/app/test/AppTest/Service/Lpa/ResolveActor/CombinedLpaHasActorTraitTest.php b/service-api/app/test/AppTest/Service/Lpa/ResolveActor/CombinedLpaHasActorTraitTest.php
new file mode 100644
index 0000000000..463f85f155
--- /dev/null
+++ b/service-api/app/test/AppTest/Service/Lpa/ResolveActor/CombinedLpaHasActorTraitTest.php
@@ -0,0 +1,214 @@
+<?php
+
+declare(strict_types=1);
+
+namespace AppTest\Service\Lpa\ResolveActor;
+
+use App\Entity\Sirius\SiriusLpa;
+use App\Enum\LifeSustainingTreatment;
+use App\Enum\LpaType;
+use App\Service\Lpa\ResolveActor\ActorType;
+use App\Service\Lpa\ResolveActor\HasActorInterface;
+use App\Service\Lpa\ResolveActor\LpaActor;
+use App\Service\Lpa\ResolveActor\SiriusHasActorTrait;
+use App\Service\Lpa\SiriusPerson;
+use DateTimeImmutable;
+use PHPUnit\Framework\Attributes\Test;
+use PHPUnit\Framework\TestCase;
+
+class CombinedLpaHasActorTraitTest extends TestCase
+{
+    private HasActorInterface $mock;
+
+    public function setUp(): void
+    {
+        $this->mock = new SiriusLpa(
+            $applicationHasGuidance     = false,
+            $applicationHasRestrictions = false,
+            $applicationType            = 'Classic',
+            $attorneyActDecisions       = null,
+            $attorneys                  = [
+                [
+                    'addressLine1' => '9 high street',
+                    'addressLine2' => '',
+                    'addressLine3' => '',
+                    'country'      => '',
+                    'county'       => '',
+                    'dob'          => null,
+                    'email'        => '',
+                    'firstname'    => 'A',
+                    'firstnames'   => null,
+                    'name'         => null,
+                    'otherNames'   => null,
+                    'postcode'     => 'DN37 5SH',
+                    'surname'      => 'B',
+                    'systemStatus' => '1',
+                    'town'         => '',
+                    'type'         => 'Primary',
+                    'uId'          => '345678901',
+                ],
+                [
+                    'addressLine1' => '',
+                    'addressLine2' => '',
+                    'addressLine3' => '',
+                    'country'      => '',
+                    'county'       => '',
+                    'dob'          => null,
+                    'email'        => 'XXXXX',
+                    'firstname'    => 'B',
+                    'firstnames'   => null,
+                    'name'         => null,
+                    'otherNames'   => null,
+                    'postcode'     => '',
+                    'surname'      => 'C',
+                    'systemStatus' => '1',
+                    'town'         => '',
+                    'type'         => 'Primary',
+                    'uId'          => '456789012',
+                ],
+                [
+                    'addressLine1' => '',
+                    'addressLine2' => '',
+                    'addressLine3' => '',
+                    'country'      => '',
+                    'county'       => '',
+                    'dob'          => null,
+                    'email'        => 'XXXXX',
+                    'firstname'    => 'C',
+                    'firstnames'   => null,
+                    'name'         => null,
+                    'otherNames'   => null,
+                    'postcode'     => '',
+                    'surname'      => 'D',
+                    'systemStatus' => '1',
+                    'town'         => '',
+                    'type'         => 'Primary',
+                    'uId'          => '567890123',
+                ],
+            ],
+            $caseSubtype                = LpaType::fromShortName('personal-welfare'),
+            $channel                    = null,
+            $dispatchDate               = null,
+            $donor                      = (object)[
+                'addressLine1' => '81 Front Street',
+                'addressLine2' => 'LACEBY',
+                'addressLine3' => '',
+                'country'      => '',
+                'county'       => '',
+                'dob'          => null,
+                'email'        => 'RachelSanderson@opgtest.com',
+                'firstname'    => 'Rachel',
+                'firstnames'   => null,
+                'name'         => null,
+                'otherNames'   => null,
+                'postcode'     => 'DN37 5SH',
+                'surname'      => 'Sanderson',
+                'systemStatus' => null,
+                'town'         => '',
+                'type'         => 'Primary',
+                'uId'          => '123456789',
+                'linked'       => [
+                    [
+                        'id'  => 1,
+                        'uId' => '123456789',
+                    ],
+                    [
+                        'id'  => 2,
+                        'uId' => '234567890',
+                    ],
+                ],
+            ],
+            $hasSeveranceWarning        = null,
+            $invalidDate                = null,
+            $lifeSustainingTreatment    = LifeSustainingTreatment::fromShortName('Option A'),
+            $lpaDonorSignatureDate      = new DateTimeImmutable('2012-12-12'),
+            $lpaIsCleansed              = true,
+            $onlineLpaId                = 'A33718377316',
+            $receiptDate                = new DateTimeImmutable('2014-09-26'),
+            $registrationDate           = new DateTimeImmutable('2019-10-10'),
+            $rejectedDate               = null,
+            $replacementAttorneys       = [],
+            $status                     = 'Registered',
+            $statusDate                 = null,
+            $trustCorporations          = [
+                [
+                    'addressLine1' => 'Street 1',
+                    'addressLine2' => 'Street 2',
+                    'addressLine3' => 'Street 3',
+                    'country'      => 'GB',
+                    'county'       => 'County',
+                    'dob'          => null,
+                    'email'        => null,
+                    'firstname'    => 'trust',
+                    'firstnames'   => null,
+                    'name'         => 'A',
+                    'otherNames'   => null,
+                    'postcode'     => 'ABC 123',
+                    'surname'      => 'test',
+                    'systemStatus' => '1',
+                    'town'         => 'Town',
+                    'type'         => 'Primary',
+                    'uId'          => '678901234',
+                ],
+                [
+                    'addressLine1' => 'Street 1',
+                    'addressLine2' => 'Street 2',
+                    'addressLine3' => 'Street 3',
+                    'country'      => 'GB',
+                    'county'       => 'County',
+                    'dob'          => null,
+                    'email'        => null,
+                    'firstname'    => 'trust',
+                    'firstnames'   => null,
+                    'name'         => 'B',
+                    'otherNames'   => null,
+                    'postcode'     => 'ABC 123',
+                    'surname'      => 'test',
+                    'systemStatus' => '1',
+                    'town'         => 'Town',
+                    'type'         => 'Primary',
+                    'uId'          => '789012345',
+                ],
+            ],
+            $uId                        = '700000000047',
+            $withdrawnDate              = null
+        );
+    }
+
+    #[Test]
+    public function does_not_find_nonexistant_actor(): void
+    {
+        $result = $this->mock->hasActor('012345678');
+
+        $this->assertNull($result);
+    }
+
+    #[Test]
+    public function finds_a_donor_actor(): void
+    {
+        $result = $this->mock->hasActor('123456789');
+
+        $this->assertInstanceOf(LpaActor::class, $result);
+        $this->assertEquals(ActorType::DONOR, $result->actorType);
+    }
+
+    #[Test]
+    public function finds_an_attorney_actor(): void
+    {
+        $result = $this->mock->hasActor('456789012');
+
+        $this->assertInstanceOf(LpaActor::class, $result);
+        $this->assertEquals('B', $result->actor['firstname']);
+        $this->assertEquals(ActorType::ATTORNEY, $result->actorType);
+    }
+
+    #[Test]
+    public function finds_a_trust_corporation_actor(): void
+    {
+        $result = $this->mock->hasActor('789012345');
+
+        $this->assertInstanceOf(LpaActor::class, $result);
+        $this->assertEquals('B', $result->actor['name']);
+        $this->assertEquals(ActorType::TRUST_CORPORATION, $result->actorType);
+    }
+}