diff --git a/GitFyle.Core.Api.Tests.Unit/Services/Foundations/Repositories/RepositoryServiceTests.Exceptions.Add.cs b/GitFyle.Core.Api.Tests.Unit/Services/Foundations/Repositories/RepositoryServiceTests.Exceptions.Add.cs
index 8bbddf81..fa645600 100644
--- a/GitFyle.Core.Api.Tests.Unit/Services/Foundations/Repositories/RepositoryServiceTests.Exceptions.Add.cs
+++ b/GitFyle.Core.Api.Tests.Unit/Services/Foundations/Repositories/RepositoryServiceTests.Exceptions.Add.cs
@@ -177,6 +177,62 @@ await Assert.ThrowsAsync<RepositoryDependencyException>(
             this.storageBrokerMock.VerifyNoOtherCalls();
         }
 
+        [Fact]
+        public async Task ShouldThrowDependencyValidationExceptionOnAddIfForeignKeyExceptionOccursAndLogItAsync()
+        {
+            // given
+            Repository someRepository = CreateRandomRepository();
+            string someMessage = GetRandomString();
+
+            var foreignKeyConstraintConflictException =
+                new ForeignKeyConstraintConflictException(someMessage);
+            
+            var invalidRepositoryReferenceException =
+                new InvalidRepositoryReferenceException(
+                    message: "Invalid repository reference error occurred.",
+                    innerException: foreignKeyConstraintConflictException,
+                    data: foreignKeyConstraintConflictException.Data);
+            
+            var expectedRepositoryDependencyValidationException =
+                new RepositoryDependencyValidationException(
+                    message: "Repository validation error occurred, fix errors and try again.",
+                    innerException: invalidRepositoryReferenceException,
+                    data: invalidRepositoryReferenceException.Data);
+            
+            this.dateTimeBrokerMock.Setup(broker =>
+                broker.GetCurrentDateTimeOffsetAsync())
+                    .ThrowsAsync(foreignKeyConstraintConflictException);
+            
+            // when
+            ValueTask<Repository> addRepositoryTask =
+                this.repositoryService.AddRepositoryAsync(someRepository);
+            
+            RepositoryDependencyValidationException actualRepositoryDependencyValidationException =
+                await Assert.ThrowsAsync<RepositoryDependencyValidationException>(
+                    addRepositoryTask.AsTask);
+            
+            // then
+            actualRepositoryDependencyValidationException.Should()
+                .BeEquivalentTo(expectedRepositoryDependencyValidationException);
+            
+            this.dateTimeBrokerMock.Verify(broker =>
+                broker.GetCurrentDateTimeOffsetAsync(),
+                    Times.Once);
+            
+            this.loggingBrokerMock.Verify(broker =>
+                broker.LogErrorAsync(It.Is(SameExceptionAs(
+                    expectedRepositoryDependencyValidationException))),
+                        Times.Once);
+            
+            this.storageBrokerMock.Verify(broker =>
+                broker.InsertRepositoryAsync(It.IsAny<Repository>()),
+                    Times.Never);
+            
+            this.dateTimeBrokerMock.VerifyNoOtherCalls();
+            this.loggingBrokerMock.VerifyNoOtherCalls();
+            this.storageBrokerMock.VerifyNoOtherCalls();
+        }
+
         [Fact]
         public async Task ShouldThrowServiceExceptionOnAddIfServiceErrorOccurredAndLogItAsync()
         {
diff --git a/GitFyle.Core.Api.Tests.Unit/Services/Foundations/Repositories/RepositoryServiceTests.Exceptions.Modify.cs b/GitFyle.Core.Api.Tests.Unit/Services/Foundations/Repositories/RepositoryServiceTests.Exceptions.Modify.cs
index 39396c07..4b51cd98 100644
--- a/GitFyle.Core.Api.Tests.Unit/Services/Foundations/Repositories/RepositoryServiceTests.Exceptions.Modify.cs
+++ b/GitFyle.Core.Api.Tests.Unit/Services/Foundations/Repositories/RepositoryServiceTests.Exceptions.Modify.cs
@@ -4,6 +4,7 @@
 
 using System;
 using System.Threading.Tasks;
+using EFxceptions.Models.Exceptions;
 using FluentAssertions;
 using GitFyle.Core.Api.Models.Foundations.Repositories;
 using GitFyle.Core.Api.Models.Foundations.Repositories.Exceptions;
@@ -189,6 +190,63 @@ await Assert.ThrowsAsync<RepositoryDependencyValidationException>(
             this.storageBrokerMock.VerifyNoOtherCalls();
         }
 
+        [Fact]
+        public async Task ShouldThrowDependencyValidationExceptionOnModifyIfForeignKeyErrorOccursAndLogItAsync()
+        {
+            // given
+            Repository someRepository = CreateRandomRepository();
+            string someMessage = GetRandomString();
+            string exceptionMessage = someMessage;
+
+            var foreignKeyConstraintConflictException =
+                new ForeignKeyConstraintConflictException(exceptionMessage);
+
+            var invalidRepositoryReferenceException =
+                new InvalidRepositoryReferenceException(
+                    message: "Invalid repository reference error occurred.",
+                    innerException: foreignKeyConstraintConflictException,
+                    data: foreignKeyConstraintConflictException.Data);
+
+            var expectedRepositoryDependencyValidationException =
+                new RepositoryDependencyValidationException(
+                    message: "Repository validation error occurred, fix errors and try again.",
+                    innerException: invalidRepositoryReferenceException,
+                    data: invalidRepositoryReferenceException.Data);
+
+            this.dateTimeBrokerMock.Setup(broker =>
+                broker.GetCurrentDateTimeOffsetAsync())
+                    .ThrowsAsync(foreignKeyConstraintConflictException);
+
+            // when
+            ValueTask<Repository> modifyRepositoryTask =
+                this.repositoryService.ModifyRepositoryAsync(someRepository);
+
+            RepositoryDependencyValidationException actualRepositoryDependencyValidationException =
+                await Assert.ThrowsAsync<RepositoryDependencyValidationException>(
+                    modifyRepositoryTask.AsTask);
+
+            // then
+            actualRepositoryDependencyValidationException.Should()
+                .BeEquivalentTo(expectedRepositoryDependencyValidationException);
+
+            this.dateTimeBrokerMock.Verify(broker =>
+                broker.GetCurrentDateTimeOffsetAsync(),
+                    Times.Once);
+
+            this.loggingBrokerMock.Verify(broker =>
+                broker.LogErrorAsync(It.Is(SameExceptionAs(
+                    expectedRepositoryDependencyValidationException))),
+                        Times.Once);
+
+            this.storageBrokerMock.Verify(broker =>
+                broker.InsertRepositoryAsync(It.IsAny<Repository>()),
+                    Times.Never);
+
+            this.dateTimeBrokerMock.VerifyNoOtherCalls();
+            this.loggingBrokerMock.VerifyNoOtherCalls();
+            this.storageBrokerMock.VerifyNoOtherCalls();
+        }
+
         [Fact]
         public async Task ShouldThrowServiceExceptionOnModifyIfServiceErrorOccursAndLogItAsync()
         {
diff --git a/GitFyle.Core.Api/Models/Foundations/Repositories/Exceptions/InvalidRepositoryReferenceException.cs b/GitFyle.Core.Api/Models/Foundations/Repositories/Exceptions/InvalidRepositoryReferenceException.cs
new file mode 100644
index 00000000..1777f435
--- /dev/null
+++ b/GitFyle.Core.Api/Models/Foundations/Repositories/Exceptions/InvalidRepositoryReferenceException.cs
@@ -0,0 +1,17 @@
+// ----------------------------------------------------------------------------------
+// Copyright (c) The Standard Organization: A coalition of the Good-Hearted Engineers
+// ----------------------------------------------------------------------------------
+
+using System;
+using System.Collections;
+using Xeptions;
+
+namespace GitFyle.Core.Api.Models.Foundations.Repositories.Exceptions
+{
+    public class InvalidRepositoryReferenceException : Xeption
+    {
+        public InvalidRepositoryReferenceException(string message, Exception innerException, IDictionary data)
+            : base(message, innerException, data)
+        { }
+    }
+}
\ No newline at end of file
diff --git a/GitFyle.Core.Api/Services/Foundations/Repositories/RepositoryService.Exceptions.cs b/GitFyle.Core.Api/Services/Foundations/Repositories/RepositoryService.Exceptions.cs
index 145e9472..e469983b 100644
--- a/GitFyle.Core.Api/Services/Foundations/Repositories/RepositoryService.Exceptions.cs
+++ b/GitFyle.Core.Api/Services/Foundations/Repositories/RepositoryService.Exceptions.cs
@@ -55,6 +55,16 @@ private async ValueTask<Repository> TryCatch(ReturningRepositoryFunction returni
 
                 throw await CreateAndLogDependencyValidationExceptionAsync(alreadyExistsRepositoryException);
             }
+            catch (ForeignKeyConstraintConflictException foreignKeyConstraintConflictException)
+            {
+                var invalidRepositoryReferenceException =
+                    new InvalidRepositoryReferenceException(
+                        message: "Invalid repository reference error occurred.",
+                        innerException: foreignKeyConstraintConflictException,
+                        data: foreignKeyConstraintConflictException.Data);
+
+                throw await CreateAndLogDependencyValidationExceptionAsync(invalidRepositoryReferenceException);
+            }
             catch (DbUpdateConcurrencyException dbUpdateConcurrencyException)
             {
                 var concurrencyGemException =