How to remove my phone number from another account.

Hi,

I managed to get scammed into giving my auth code sent to my phone to someone over Instagram and they used that to buy stuff via my phone bill.

I tried to browse MS articles and there is no useful answer in there any where. What I found is basically "we can't help you unless you own the account."
Which is wild. If my phone number get added to an account I don't own it just hard locked to that account, because no one get scammed ever apparently.
There is a limit so they didn't managed to use more than 100$, but i would really like my number NOT to be assigned to an account I don't own.

How can I get that number removed from the other account?