FritzBox integration with user/pw instead of just pw

Hi all,
after I enabled user and password for authentication in my FritzBox (OS 7.2), the integration is not working anymore.

2020-10-02 20:54:09 ERROR (MainThread) [homeassistant.config_entries] Error setting up entry FRITZ!Box 7590 for fritzbox
Traceback (most recent call last):
  File "/usr/src/homeassistant/homeassistant/config_entries.py", line 228, in async_setup
    result = await component.async_setup_entry(hass, self)  # type: ignore
  File "/usr/src/homeassistant/homeassistant/components/fritzbox/__init__.py", line 79, in async_setup_entry
    await hass.async_add_executor_job(fritz.login)
  File "/usr/local/lib/python3.8/concurrent/futures/thread.py", line 57, in run
    result = self.fn(*self.args, **self.kwargs)
  File "/usr/local/lib/python3.8/site-packages/pyfritzhome/fritzhome.py", line 118, in login
    raise LoginError(self._user)
pyfritzhome.errors.LoginError: login for user="admin" failed

The reason seems to be that I now have a different username and password as before. The provided credentials in the config don’t match the stored credentials in config/.storage.
What would be the best solution? Delete and readding the integration? Or can the user/pw be changed in the core.config_entries file?

Is it not possible to switch the FB back to pw authentication, modify the settings in the FB integration and switch the authentication back again to user/pw?

Just and idea…

The integration config without a user/pw does not require to enter the data. The FritzBox will be discovered automatically (as stated on the integration documentatino). That works great. In this scenario there is no username to fill in.

Only when switching to user/pw authentication, the entered values are not picked up.

I think the integration through the UI didn’t exist when I started using HA, so I configured mine in YAML.

This is what I have in sensor.yaml and works with a user/pw config on my FB.

- platform: fritzbox_callmonitor
  name: Phone
  host: 172.16.0.2
  username: !secret FB_user
  password: !secret FB_password

HTH