I recently played some ranked matches with a teammate. I wanted to switch from my Warri to my Engi during the warmup, but i got the errormessage: "You cannot join the PvP game in progress because your character has changed". Switch to the Guard resulted in the same Error. So I had to switch back to my Warrior and played the match with him. Our team had no Guards or Engineers at all, so it couldn´t be the Class-Stack-Prevention.
A screenshot of the error message is here: https://imgur.com/a/3eeEQyy
Does anyone have an idea whats the problem here?