Unable to join or host experiences

I tried to play some experiences and in the beginning everything seemed to work fine. But when I tried to join a server, it wouldn't let me with the error message "Unable to join..." regardless of how full the server was. Sometimes I could join but were kicked out to the main menu right after the loading screen without any error message. After I unsuccessfully tried to join a few servers, the server browser stopped working completely and is loading indefinitely, again, without any error message. This is the same for every Experience I try to join. Also, I can't host my own server. At the beginning it gave me the error message "Server slots are full" but now just nothing happens when I click the host button. We were all promised one server slot, but most people can't use it. Please fix this issue.

I'm playing on Steam PC in EU Region. Build ID: 20373067