So wait ... First of all just wanna say that grammar Is on point 10/10 . "I think you didn't ban me" where you high when making this post?
If your using windows try using the application snipping tool to take a screenshot of the problem as it will be easy to see what's going on. It just makes things alot easy to understand it rather then trying to describe it.
What caught me off guard was that you said "I even tried to join with alphapizza's account" are you saying that you have his account if so why do you even have it. Reading this just hurts my head. ANOTHER thing is because this is a ban related thing you should make an ban appeal application or a support ticket since higher staff will be reviewing them.