Sign in problems

Question

First off this is absolutely ridiculous the steps you have to do just to get into your account. I need to update my phone and I can’t do that cause I need a code from my old phone number that I don’t have so I tried to update the security info but now I have to wait a month for that to take effect!!! That’s ridiculous… I’m trying to cancel that but YOU NEED YOUR OLD PHONE NUMBER how does that even make sense I’m changing it for a reason why would I use the same number if I’m changing the security I just need help so I can login my Xbox please help!!!!!