I've seen all the post on how to regain access to the disk, but how do I do that without erasing and loosing all my Time machine backups?

I'm having the same problem with my MacBook Pro M1 max. I have a 2TB external drive I was using with Time machine backups that I can No longer mount. Even disk utility won't allow the disk to be erased and reformatted. I would have thought that apple would have the solution by now seeing how so many have encountered this problem. can someone please help????