Phone number is already in use with another account

I am trying to register my phone number with a new Apple ID that I made however when I do this it says it is "already in use with another account". The phone number is already removed from my previous Apple ID (I believe?) as I deregistered it from iMessage and it's not listed under that account's reachable information. Is there a way I can check what accounts my phone number is registered with? Or automatically remove my number from any accounts by way of text confirmation or something similar to that? Any help is appreciated, thanks!