Paid them for four years. If I had known they were going to delete the backups in just over one month, I wouldn’t have risked that.

Lost everything when they deleted the backups. They turned off the server on the same day, and it was running fine right up until then. Zero warning other than the emails I didn’t see.

So you didn't pay attention to the emails, didn't pay them, then get mad when they don't store data for free for you? Ok...

How should they get ahold of you? A call that you don't answer? A letter that goes unopened? African swallow laden with a note that you don't see?

Keep backups elsewhere. Regardless of cloud provider or payment terms or whatever. 3-2-1 backups.

Store backups for a little while and charge a fee (high enough to make this service profitable) to release them.

A customer for 4 years and they delete everything after 5 weeks? Can you really defend that? It's pretty clearly a bad policy. You're being facetious about other contact methods, but I think that's a great idea. Allow users to add a phone number. Some people have faulty spam email blockers.