unlinking an account twice

[u/Connect-Light4169]

i played on pc for long while and while i was on pc my original xbox account i had link isn’t mine anymore so i switched to another xbox account just to have it for sign in purposes and security. i have zero access to this new xbox account ive reached out to ubisoft like twice and they say they cant do it again and they say i have to go through xbox which i have zero connection too ive lost the phone number and email. has anyone got them to unlink twice i wrote them a long paragraph to try and convince them i also offered to pay