Get rid of user badge in notification bar

I investigated the “multiple user” feature on my phone for a friend and clicked on the guest user. From that point on there was a user badge in the status bar on my lock screen and when I pull down the notification bar (the one on the lock screen annoys me more):

How can I get rid of this badge? I have no intention to run a second user on my Fairphone 3.

Should be the reverse case of this problem:

Go to settings → users
There the Guest account should be listed.
Change to this Guest account
Again go to settings → users
Then you should get the option to remove the guest account.
If I recall it right, that is.
I right now don’t have my phone at hand.
Edit: I guess if there is no guest account that the icon disappears as well.

Best luck.