Need help removing old account and unlinking Xbox for new account

Hey there, hoping support can message me so I can explain removing an old account after deleting the email it’s connected to. It won’t let me make any changes and I can’t connect the new account I made to my Xbox. If Support could message me so I can get it fixed I would appreciate it! Thank you.

Unfortunately, many of us are in the same boat for similar issues. Contacted multiple times the support for the last 4days, no response so far. 3/4 of the emails are bouncing back because their email system bug/is full.
All this for 1 simple click to unlink an account, a basic feature... really dumb and frustrating.

If you have any news, let us know ;)

Literally in the same boat and I am beyond frustrated I bought 2 copies one for xbox and one for PC and I need them linked.

Customer support non-existant.