diff --git a/RestaurantReservation.Test/GenericControllerFunctionalTests.cs b/RestaurantReservation.Test/GenericControllerFunctionalTests.cs
new file mode 100644
index 0000000..631e8e0
--- /dev/null
+++ b/RestaurantReservation.Test/GenericControllerFunctionalTests.cs
@@ -0,0 +1,62 @@
+using Microsoft.Extensions.DependencyInjection;
+using RestaurantReservation.Presentation.Interfaces;
+using RestaurantReservation.Test.Data;
+using RestaurantReservation.Test.Fixtures;
+using FluentAssertions;
+
+namespace RestaurantReservation.Test;
+
+public class ProgramFunctionalTests : IClassFixture<FullTestSetupFixture>
+{
+    private readonly IGenericController _genericController;
+
+    public ProgramFunctionalTests(FullTestSetupFixture fullTestSetupFixture)
+    {
+        _genericController = fullTestSetupFixture.ServiceProvider.GetRequiredService<IGenericController>();
+    }
+
+    [Fact]
+    public async Task ListManagers_ShouldReturnCorrectData()
+    {
+        var managers = await _genericController.ListManagers().ToListAsync();
+        managers.Count.Should().Be(1);
+        managers[0].Should().BeEquivalentTo(ModelsData.Employees().ToList()[0]);
+    }
+
+    [Fact]
+    public async Task GetReservationsByCustomer_ShouldReturnCorrectData()
+    {
+        var reservations = await _genericController.GetReservationsByCustomer(1).ToListAsync();
+        reservations.Count.Should().Be(1);
+        reservations[0].Should().BeEquivalentTo(ModelsData.Reservations().ToList()[0]);
+    }
+
+    [Fact]
+    public async Task ListOrdersAndMenuItems_ShouldReturnCorrectData()
+    {
+        var pairs = await _genericController.ListOrdersAndMenuItems(1).ToListAsync();
+        pairs.Count.Should().Be(1);
+
+        var (order, menuItems) = pairs[0];
+        order.Should().BeEquivalentTo(ModelsData.Orders().ToList()[0]);
+
+        var menuItemList = await menuItems.ToListAsync();
+        menuItemList.Count.Should().Be(1);
+        menuItemList[0].Should().BeEquivalentTo(ModelsData.MenuItems().ToList()[0]);
+    }
+
+    [Fact]
+    public async Task ListOrderedMenuItems_ShouldReturnCorrectData()
+    {
+        var menuItems = await _genericController.ListOrderedMenuItems(1).ToListAsync();
+        menuItems.Count.Should().Be(1);
+        menuItems[0].Should().BeEquivalentTo(ModelsData.MenuItems().ToList()[0]);
+    }
+
+    [Fact]
+    public async Task CalculateAverageOrderAmount_ShouldReturnCorrectData()
+    {
+        var average = await _genericController.CalculateAverageOrderAmount(1);
+        average.Should().BeApproximately(45.9, 1e-6);
+    }
+}
\ No newline at end of file
diff --git a/RestaurantReservation.Test/RestaurantReservation.Test.csproj b/RestaurantReservation.Test/RestaurantReservation.Test.csproj
index cc1e79c..d3a6752 100644
--- a/RestaurantReservation.Test/RestaurantReservation.Test.csproj
+++ b/RestaurantReservation.Test/RestaurantReservation.Test.csproj
@@ -18,6 +18,7 @@
         <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="8.0.4" />
         <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="8.0.0" />
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0"/>
+        <PackageReference Include="System.Linq.Async" Version="6.0.1" />
         <PackageReference Include="xunit" Version="2.5.3"/>
         <PackageReference Include="xunit.runner.visualstudio" Version="2.5.3"/>
     </ItemGroup>
diff --git a/RestaurantReservation/Presentation/Controllers/GenericController.cs b/RestaurantReservation/Presentation/Controllers/GenericController.cs
index 6583e50..1079c6c 100644
--- a/RestaurantReservation/Presentation/Controllers/GenericController.cs
+++ b/RestaurantReservation/Presentation/Controllers/GenericController.cs
@@ -47,12 +47,13 @@ public async IAsyncEnumerable<Reservation> GetReservationsByCustomer(int custome
 
         await foreach (var order in orders.AsAsyncEnumerable())
         {
-            var menuItems = context.OrderItems
+            var menuItems = await context.OrderItems
                 .Where(oi => oi.OrderId == order.OrderId)
                 .Select(od => od.MenuItem)
-                .AsAsyncEnumerable();
+                .Distinct()
+                .ToListAsync();
 
-            yield return (order, menuItems);
+            yield return (order, menuItems.ToAsyncEnumerable());
         }
     }