LDAP-integration Nextcloud works but password change doenst

Hey there! i am looking for help since i am kinda stuck with my Problem:

I run a docker Nextcloud container behind a nginx-reverse-proxy. The Nextcloud container is also connected to a Microsoft Active Directory via ldap and i got my users up and running. Usersync and login works. Now the strange problem: If i try to realize Password change via GUI it gives me a green Tick-checkbox but the password is getting updated(i see changes in AD) but i still cannot access the nextcloud install with the new password - just the old works.

Could anyone assist me here ?

I did a little more research. The password that appears in the attributes is simply a string that is added to the user and is not actually stored as a “password”.