diff --git a/CleanArchitecture.Api/Controllers/UserController.cs b/CleanArchitecture.Api/Controllers/UserController.cs
index aa66217..3aac047 100644
--- a/CleanArchitecture.Api/Controllers/UserController.cs
+++ b/CleanArchitecture.Api/Controllers/UserController.cs
@@ -56,7 +56,6 @@ public sealed class UserController : ApiController
     }
 
     [HttpPost]
-    [AllowAnonymous]
     [SwaggerOperation("Create a new user")]
     [SwaggerResponse(200, "Request successful", typeof(ResponseMessage<Guid>))]
     public async Task<IActionResult> CreateUserAsync([FromBody] CreateUserViewModel viewModel)
diff --git a/CleanArchitecture.Domain.Tests/CommandHandler/User/CreateUser/CreateUserCommandHandlerTests.cs b/CleanArchitecture.Domain.Tests/CommandHandler/User/CreateUser/CreateUserCommandHandlerTests.cs
index 0151fd4..0f0e7d6 100644
--- a/CleanArchitecture.Domain.Tests/CommandHandler/User/CreateUser/CreateUserCommandHandlerTests.cs
+++ b/CleanArchitecture.Domain.Tests/CommandHandler/User/CreateUser/CreateUserCommandHandlerTests.cs
@@ -1,7 +1,9 @@
 using System;
 using CleanArchitecture.Domain.Commands.Users.CreateUser;
+using CleanArchitecture.Domain.Enums;
 using CleanArchitecture.Domain.Errors;
 using CleanArchitecture.Domain.Events.User;
+using NSubstitute;
 using Xunit;
 
 namespace CleanArchitecture.Domain.Tests.CommandHandler.User.CreateUser;
@@ -13,7 +15,6 @@ public sealed class CreateUserCommandHandlerTests
     [Fact]
     public void Should_Create_User()
     {
-        // Todo: Fix tests
         _fixture.SetupCurrentUser();
 
         var user = _fixture.SetupUser();
@@ -60,6 +61,41 @@ public sealed class CreateUserCommandHandlerTests
                 DomainErrorCodes.User.UserAlreadyExists,
                 $"There is already a user with Id {command.UserId}");
     }
+    
+    [Fact]
+    public void Should_Not_Create_Already_Existing_Email()
+    {
+        _fixture.SetupCurrentUser();
+
+        _fixture.UserRepository
+            .GetByEmailAsync(Arg.Is<string>(y => y == "test@email.com"))
+            .Returns(new Entities.User(
+                Guid.NewGuid(),
+                Guid.NewGuid(),
+                "max@mustermann.com",
+                "Max",
+                "Mustermann",
+                "Password",
+                UserRole.User));
+
+        var command = new CreateUserCommand(
+            Guid.NewGuid(),
+            Guid.NewGuid(),
+            "test@email.com",
+            "Test",
+            "Email",
+            "Po=PF]PC6t.?8?ks)A6W");
+
+        _fixture.CommandHandler.Handle(command, default).Wait();
+
+        _fixture
+            .VerifyNoCommit()
+            .VerifyNoRaisedEvent<UserCreatedEvent>()
+            .VerifyAnyDomainNotification()
+            .VerifyExistingNotification(
+                DomainErrorCodes.User.UserAlreadyExists,
+                $"There is already a user with email {command.Email}");
+    }
 
     [Fact]
     public void Should_Not_Create_User_Tenant_Does_Not_Exist()
diff --git a/CleanArchitecture.Domain.Tests/CommandHandler/User/CreateUser/CreateUserCommandTestFixture.cs b/CleanArchitecture.Domain.Tests/CommandHandler/User/CreateUser/CreateUserCommandTestFixture.cs
index 812257f..3cf3a09 100644
--- a/CleanArchitecture.Domain.Tests/CommandHandler/User/CreateUser/CreateUserCommandTestFixture.cs
+++ b/CleanArchitecture.Domain.Tests/CommandHandler/User/CreateUser/CreateUserCommandTestFixture.cs
@@ -1,7 +1,6 @@
 using System;
 using CleanArchitecture.Domain.Commands.Users.CreateUser;
 using CleanArchitecture.Domain.Enums;
-using CleanArchitecture.Domain.Interfaces;
 using CleanArchitecture.Domain.Interfaces.Repositories;
 using NSubstitute;
 
@@ -10,15 +9,13 @@ namespace CleanArchitecture.Domain.Tests.CommandHandler.User.CreateUser;
 public sealed class CreateUserCommandTestFixture : CommandHandlerFixtureBase
 {
     public CreateUserCommandHandler CommandHandler { get; }
-    private IUserRepository UserRepository { get; }
+    public IUserRepository UserRepository { get; }
     private ITenantRepository TenantRepository { get; }
-    private IUser User { get; }
 
     public CreateUserCommandTestFixture()
     {
         UserRepository = Substitute.For<IUserRepository>();
         TenantRepository = Substitute.For<ITenantRepository>();
-        User = Substitute.For<IUser>();
 
         CommandHandler = new CreateUserCommandHandler(
             Bus,
diff --git a/CleanArchitecture.Domain.Tests/CommandHandler/User/DeleteUser/DeleteUserCommandHandlerTests.cs b/CleanArchitecture.Domain.Tests/CommandHandler/User/DeleteUser/DeleteUserCommandHandlerTests.cs
index 1e65782..95d2569 100644
--- a/CleanArchitecture.Domain.Tests/CommandHandler/User/DeleteUser/DeleteUserCommandHandlerTests.cs
+++ b/CleanArchitecture.Domain.Tests/CommandHandler/User/DeleteUser/DeleteUserCommandHandlerTests.cs
@@ -42,4 +42,24 @@ public sealed class DeleteUserCommandHandlerTests
                 ErrorCodes.ObjectNotFound,
                 $"There is no user with Id {command.UserId}");
     }
+    
+    [Fact]
+    public void Should_Not_Delete_User_Insufficient_Permissions()
+    {
+        var user = _fixture.SetupUser();
+
+        _fixture.SetupCurrentUser();
+
+        var command = new DeleteUserCommand(user.Id);
+
+        _fixture.CommandHandler.Handle(command, default).Wait();
+
+        _fixture
+            .VerifyNoCommit()
+            .VerifyNoRaisedEvent<UserDeletedEvent>()
+            .VerifyAnyDomainNotification()
+            .VerifyExistingNotification(
+                ErrorCodes.InsufficientPermissions,
+                $"No permission to delete user {command.UserId}");
+    }
 }
\ No newline at end of file
diff --git a/CleanArchitecture.Domain.Tests/CommandHandler/User/DeleteUser/DeleteUserCommandTestFixture.cs b/CleanArchitecture.Domain.Tests/CommandHandler/User/DeleteUser/DeleteUserCommandTestFixture.cs
index 96f7d5d..bdd73f9 100644
--- a/CleanArchitecture.Domain.Tests/CommandHandler/User/DeleteUser/DeleteUserCommandTestFixture.cs
+++ b/CleanArchitecture.Domain.Tests/CommandHandler/User/DeleteUser/DeleteUserCommandTestFixture.cs
@@ -40,4 +40,9 @@ public sealed class DeleteUserCommandTestFixture : CommandHandlerFixtureBase
 
         return user;
     }
+    
+    public void SetupCurrentUser()
+    {
+        User.GetUserRole().Returns(UserRole.User);
+    }
 }
\ No newline at end of file
diff --git a/CleanArchitecture.IntegrationTests/Infrastructure/CleanArchitectureWebApplicationFactory.cs b/CleanArchitecture.IntegrationTests/Infrastructure/CleanArchitectureWebApplicationFactory.cs
index 6328d21..da21af7 100644
--- a/CleanArchitecture.IntegrationTests/Infrastructure/CleanArchitectureWebApplicationFactory.cs
+++ b/CleanArchitecture.IntegrationTests/Infrastructure/CleanArchitectureWebApplicationFactory.cs
@@ -57,7 +57,7 @@ public sealed class CleanArchitectureWebApplicationFactory : WebApplicationFacto
                 {
                     options.DefaultAuthenticateScheme = "Testing";
                     options.DefaultChallengeScheme = "Testing";
-                }).AddTestAuthentication(options => { });
+                }).AddTestAuthentication(_ => { });
             }
 
             var sp = services.BuildServiceProvider();