How to pass credentials to sonarr correctly?

[Elekam]

So I setup sonarr in authentik. When trying to access sonarr.mydomain.com, it does try to authenticate, but fails.
In the logs, I can see that authentik tried to pass "username"

I thought it would automatically replace the 'password' with the authentik users preferred_username.
Am I misunderstanding something here? Are all the videos and threads I see just pasting their sonarr credentials into the group values?
Or are my values for some reason not being correctly replaced?

The documentation states putting these values and I assumed they were variables, but ig it just means to paste the actual credentials in?
But what if you want to have multiple different users for sonarr?

Either I have a misunderstanding or something does not work

I would greatly appreciate if anyone could clear this up for me, thank you!

[Elekam]

I just pasted the credentials into the group attributes, after which it worked. But it would seem strange to me if this is the intended way to do it?

Additionally, after authenticating and checking the logs, I see way too many lines of auth success. It seems like authentik logins/authenticates way too often? Maybe I accidentally created some kind of loop?

Edit: Curious, after trying to login anew, it passes my email as the username? Why?