diff --git a/contracts/distribution/DistributionService.sol b/contracts/distribution/DistributionService.sol
index 90acba221..67670c14b 100644
--- a/contracts/distribution/DistributionService.sol
+++ b/contracts/distribution/DistributionService.sol
@@ -191,9 +191,9 @@ contract DistributionService is
         (NftId distributionNftId, IInstance instance) = _getAndVerifyActiveDistribution();
 
         if (bytes(code).length == 0) {
-            revert ErrorDistributionServiceInvalidReferral(code);
+            revert ErrorDistributionServiceInvalidReferral();
         }
-        if (expiryAt.eqz() || expiryAt.lte(TimestampLib.blockTimestamp())) {
+        if (expiryAt.eqz() || expiryAt < TimestampLib.blockTimestamp()) {
             revert ErrorDistributionServiceExpirationInvalid(expiryAt);
         }
 
@@ -208,13 +208,13 @@ contract DistributionService is
             IDistribution.DistributorTypeInfo memory distributorTypeData = instanceReader.getDistributorTypeInfo(distributorType);
 
             if (distributorTypeData.maxReferralCount < maxReferrals) {
-                revert ErrorDistributionServiceMaxReferralsExceeded(distributorTypeData.maxReferralCount);
+                revert ErrorDistributionServiceMaxReferralsExceeded(distributorTypeData.maxReferralCount, maxReferrals);
             }
             if (distributorTypeData.minDiscountPercentage > discountPercentage) {
-                revert ErrorDistributionServiceDiscountTooLow(distributorTypeData.minDiscountPercentage.toInt(), discountPercentage.toInt());
+                revert ErrorDistributionServiceDiscountTooLow(distributorTypeData.minDiscountPercentage, discountPercentage);
             }
             if (distributorTypeData.maxDiscountPercentage < discountPercentage) {
-                revert ErrorDistributionServiceDiscountTooHigh(distributorTypeData.maxDiscountPercentage.toInt(), discountPercentage.toInt());
+                revert ErrorDistributionServiceDiscountTooHigh(distributorTypeData.maxDiscountPercentage, discountPercentage);
             }
             if (expiryAt.toInt() - TimestampLib.blockTimestamp().toInt() > distributorTypeData.maxReferralLifetime.toInt()) {
                 revert ErrorDistributionServiceExpiryTooLong(distributorTypeData.maxReferralLifetime, expiryAt);
diff --git a/contracts/distribution/IDistributionService.sol b/contracts/distribution/IDistributionService.sol
index d3dc5273e..ced5f4d76 100644
--- a/contracts/distribution/IDistributionService.sol
+++ b/contracts/distribution/IDistributionService.sol
@@ -19,11 +19,11 @@ interface IDistributionService is IService {
     error ErrorDistributionServiceParentNftIdNotInstance(NftId nftId, NftId parentNftId);
     error ErrorDistributionServiceCallerNotDistributor(address caller);
     error ErrorDistributionServiceInvalidReferralId(ReferralId referralId);
-    error ErrorDistributionServiceMaxReferralsExceeded(uint256 maxReferrals);
-    error ErrorDistributionServiceDiscountTooLow(uint256 minDiscountPercentage, uint256 discountPercentage);
-    error ErrorDistributionServiceDiscountTooHigh(uint256 maxDiscountPercentage, uint256 discountPercentage);
+    error ErrorDistributionServiceMaxReferralsExceeded(uint256 limit, uint256 maxReferrals);
+    error ErrorDistributionServiceDiscountTooLow(UFixed minDiscountPercentage, UFixed discountPercentage);
+    error ErrorDistributionServiceDiscountTooHigh(UFixed maxDiscountPercentage, UFixed discountPercentage);
     error ErrorDistributionServiceExpiryTooLong(Seconds maxReferralLifetime, Timestamp expiryAt);
-    error ErrorDistributionServiceInvalidReferral(string code);
+    error ErrorDistributionServiceInvalidReferral();
     error ErrorDistributionServiceExpirationInvalid(Timestamp expiryAt);
     error ErrorDistributionServiceCommissionTooHigh(uint256 commissionPercentage, uint256 maxCommissionPercentage);
     error ErrorDistributionServiceMinFeeTooHigh(uint256 minFee, uint256 limit);
diff --git a/test/component/distribution/Referral.t.sol b/test/component/distribution/Referral.t.sol
index c0b72c7f9..a38e62cbb 100644
--- a/test/component/distribution/Referral.t.sol
+++ b/test/component/distribution/Referral.t.sol
@@ -7,6 +7,7 @@ import {console} from "../../../lib/forge-std/src/Test.sol";
 import {FeeLib} from "../../../contracts/type/Fee.sol";
 import {IComponents} from "../../../contracts/instance/module/IComponents.sol";
 import {IDistribution} from "../../../contracts/instance/module/IDistribution.sol";
+import {IDistributionService} from "../../../contracts/distribution/IDistributionService.sol";
 import {IPolicy} from "../../../contracts/instance/module/IPolicy.sol";
 import {NftId, NftIdLib} from "../../../contracts/type/NftId.sol";
 import {POLICY} from "../../../contracts/type/ObjectType.sol";
@@ -15,8 +16,8 @@ import {ReferralTestBase} from "./ReferralTestBase.sol";
 import {RiskId, RiskIdLib} from "../../../contracts/type/RiskId.sol";
 import {SecondsLib} from "../../../contracts/type/Seconds.sol";
 import {SimpleDistribution} from "../../../contracts/examples/unpermissioned/SimpleDistribution.sol";
-import {TimestampLib} from "../../../contracts/type/Timestamp.sol";
-import {UFixedLib} from "../../../contracts/type/UFixed.sol";
+import {Timestamp, TimestampLib} from "../../../contracts/type/Timestamp.sol";
+import {UFixed, UFixedLib} from "../../../contracts/type/UFixed.sol";
 
 contract ReferralTest is ReferralTestBase {
 
@@ -307,6 +308,140 @@ contract ReferralTest is ReferralTestBase {
         vm.stopPrank();
     }
 
+    function test_createReferral_codeEmpty() public {
+        // GIVEN
+        _setupTestData(true);
+        vm.startPrank(customer);
+
+        // THEN
+        vm.expectRevert(abi.encodeWithSelector(
+            IDistributionService.ErrorDistributionServiceInvalidReferral.selector));
+
+        // WHEN
+        referralId = distribution.createReferral(
+            distributorNftId,
+            "",
+            discountPercentage,
+            maxReferrals,
+            expiryAt,
+            referralData);
+    }
+
+    function test_createReferral_expirationInvalid() public {
+        // GIVEN
+        vm.warp(500);
+        _setupTestData(true);
+        vm.startPrank(customer);
+        Timestamp tsZero = TimestampLib.zero();
+
+        // THEN
+        vm.expectRevert(abi.encodeWithSelector(
+            IDistributionService.ErrorDistributionServiceExpirationInvalid.selector,
+            0));
+
+        // WHEN
+        referralId = distribution.createReferral(
+            distributorNftId,
+            "CODE",
+            discountPercentage,
+            maxReferrals,
+            tsZero,
+            referralData);
+
+        Timestamp exp =  TimestampLib.toTimestamp(TimestampLib.blockTimestamp().toInt() - 10);
+
+        // THEN
+        vm.expectRevert(abi.encodeWithSelector(
+            IDistributionService.ErrorDistributionServiceExpirationInvalid.selector,
+            exp));
+
+        // WHEN
+        referralId = distribution.createReferral(
+            distributorNftId,
+            "CODE",
+            discountPercentage,
+            maxReferrals,
+            exp,
+            referralData);
+
+        exp =  TimestampLib.toTimestamp(TimestampLib.blockTimestamp().toInt() + maxReferralLifetime.toInt() + 10);
+
+        // THEN
+        vm.expectRevert(abi.encodeWithSelector(
+            IDistributionService.ErrorDistributionServiceExpiryTooLong.selector,
+            maxReferralLifetime,
+            exp));
+
+        // WHEN
+        referralId = distribution.createReferral(
+            distributorNftId,
+            "CODE",
+            discountPercentage,
+            maxReferrals,
+            exp,
+            referralData);
+    }
+
+    function test_createReferral_referralCountInvalid() public {
+        // GIVEN
+        _setupTestData(true);
+        vm.startPrank(customer);
+        Timestamp exp = TimestampLib.blockTimestamp().addSeconds(SecondsLib.toSeconds(10));
+
+        // THEN
+        vm.expectRevert(abi.encodeWithSelector(
+            IDistributionService.ErrorDistributionServiceMaxReferralsExceeded.selector,
+            20,
+            42));
+
+        // WHEN
+        referralId = distribution.createReferral(
+            distributorNftId,
+            "CODE",
+            discountPercentage,
+            42,
+            exp,
+            referralData);
+    }
+
+    function test_createReferral_discoundInvalid() public {
+        // GIVEN
+        _setupTestData(true);
+        vm.startPrank(customer);
+        Timestamp exp = TimestampLib.blockTimestamp().addSeconds(SecondsLib.toSeconds(10));
+        UFixed discount = UFixedLib.toUFixed(3, -2);
+
+        // THEN
+        vm.expectRevert(abi.encodeWithSelector(
+            IDistributionService.ErrorDistributionServiceDiscountTooLow.selector,
+            minDiscountPercentage,
+            discount));
+
+        // WHEN
+        referralId = distribution.createReferral(
+            distributorNftId,
+            "CODE",
+            discount,
+            15,
+            exp,
+            referralData);
+
+        // THEN
+        discount = UFixedLib.toUFixed(22, -2);
+        vm.expectRevert(abi.encodeWithSelector(
+            IDistributionService.ErrorDistributionServiceDiscountTooHigh.selector,
+            maxDiscountPercentage,
+            discount));
+
+        // WHEN
+        referralId = distribution.createReferral(
+            distributorNftId,
+            "CODE",
+            discount,
+            15,
+            exp,
+            referralData);
+    }
 
     function _setupBundle(uint256 bundleAmount) internal {