New User: Password Change if Encryption is Active

Nextcloud version: 12.0.0
Operating system and version: A managed server (some sort of Linux)
Apache or nginx version: Apache (no clue which version)
PHP version: 5.6
Is this the first time you’ve seen this error?: Yes

Can you reliably replicate it? (If so, please outline steps): Yes, see below.

Hi there,

At the moment I’ve a problem with my Nextcloud installation. I was using the instance alone for about 6 month with an active encryption. Everything works fine. Browser access, sync with iOS and Windows 10. Absolutely no problem at all.

A few days ago I created a new user. Added his username, an initial password and a specific group. This user can login but he isn’t able to change the password by himself (over the e-mail link). I think I can change it within the admin interface but we haven’t tested it yet (we meet next week).

Am I missing something? What is the intended way doing this?