Maybe it helps to save the Webtop app settings once more.
I don’t think so as you configured all apps.
Unfortunately “DB error” doesn’t say much so we need the logs please to check what was going on.
When for example the database isn’t available or has errors, user logon isn’t possible because the database is the user backend, LDAP is just used for authentication.
There’s an older post for NS7 about the DB error occuring after updates…