Microsoft account linked to a deleted e-mail address

I'm trying to help a friend who has a Microsoft account which is linked to an e-mail address that was deleted some years ago.

He had a recent problem on his laptop when Windows 11 crashed.  He went into the troubleshooting option and eventually selected the recovery option and it rebooted ok.  Interestingly, when we looked at accounts he was able to select the option to login to his administrator account and could see all details like his 365 subscription etc.

The problem is he doesn't remember his Microsoft account password and as the e-mail account linked to it is an old one that was deleted a few years ago, he is unable to receive an e-mail with the authentication code to change his password and then change the e-mail address etc.  We tried the other options where it asked lots of questions like previous passwords and even the card number for his subscription and when it reached the end, there was a message saying that facility isn't currently available.

We can't find a telephone number to speak to someone at Microsoft support and also don't know any support e-mail address.  When he tried to contact and use a chat facility it expects him to login, but he doesn't know his password so that option wasn't helpful. We are now in a situation where we don't know how to resolve the problem.

One final option which he isn't keen on is to create a new Microsoft account,cancel his credit card and get a new number, so that way they won't charge him for the 365 renewal and then create a new Microsoft account and set up a new subscription.  That is one way to work around the problem because he can't find any way to resolve the problem and so far we have found it impossible to actually speak to someone in support.

Any advice on this will be appreciated.

Thank you

David