MQTT Auth error after Snapshot Restore

Tags: #<Tag:0x00007f738fee8978>

Hi,

I moved from my Raspberry PI 3 to a brand new PI 4.
I restored a Snapshot, most things are working but I had to uninstall and reinstall some Plugins (for example Mosquitto).

But now, my HASS won’t connect to my MQTT broker I always get the following message:
Unable to connect to the MQTT broker: Connection Refused: not authorised.

All my other devices are working normaly (I can connect to the broker).

My HASS Username and Password is exactly the same like on the old PI3.
I would reset the credentials for the MQTT Integration but I configured the integration via GUI and not via config file… The only way would delete the MQTT integration and recreate them. But then I would loose all my MQTT entities…

Is there any way to solve my problem?

Venice

Edit:
In my Mosquitto log I get many of those messages:
1579957950: New connection from 172.30.33.6 on port 1883.
1579957950: Socket error on client , disconnecting.
1579957960: New connection from 172.30.33.6 on port 1883.
1579957960: Socket error on client , disconnecting.
1579957970: New connection from 172.30.33.6 on port 1883.
1579957970: Socket error on client , disconnecting.

I‘m having the exact same problem. Did you find a fix in the end?