NUnit - does not work with TestFixtureSetUp method which is not allowed on SetUpFixture

I'm trying to refactor the Integration Tests that we have, so they use a common class to create the database and data required in the database for testing in other classes in the same assembly using the [SetUpFixture] NUnit attribute.

I have:

namespace Tests;

public class TestBaseClass : SolutionBaseClass
{
    public void Setup()
    {
        base.CreateDatabase();
        base.CreateData();
    }

    public void Teardown()
    {
        base.DestroyDatabase();
    }
}

[SetUpFixture]
public class Setup : TestBaseClass
{
    [SetUp]
    public void Setup()
    {
        base.Setup();
    }

    [TearDown]
    public void Teardown()
    {
        base.Teardown();
    }
}

      

        
        
        
      

    

then the individual classes of test instruments:

namespace Tests.Services;

[TestFixture]
public class LibraryTest : TestBaseClass
{
    [TestFixtureSetUp]
    public void SetupTests()
    {
        // I know am calling the same Setup twice once from SetUpFixture and TestFixture, 
        // I have handled it so that only one Database/Data gets set up once (for safety mostly!)
        base.SetUp();

        // Other class initialisations.
    }
}

      

        
        
        
      

    

Any ideas what I am doing wrong, I suppose this is a problem with the inheritance model being used as you can tell that I am inheriting this from someone else !!

Thank.