Enabling encryption leads to problems for existing users

Nextcloud version (eg, 20.0.5): 22
Operating system and version (eg, Ubuntu 20.04): Debian 10
Apache or nginx version (eg, Apache 2.4.25): Caddy
PHP version (eg, 7.4): 8

The issue you are facing:
After enabling serverside encryption, existing users lose access to their files with the error “can not decrypt key”

Is this the first time you’ve seen this error? (Y/N): Y

So, i was asked to enable serverside encryption, and i have done so. creating new users works ok as far as i know, but multiple existing users are complaining about said error.

i have asked them to logout and login, change passwords, to no succes.
i also removed the files_encryption folder as per several topics, but this was also no succes.

Currently i am restoring from backup, but i wonder if anyone has any foolproof guide to avoid this problem in the future.