Ranked issues?

Hi there!

I’m trying to play a 2v2 ranked with a friend. Both havent finished their placement matches, yet.
If, e.g., I invite him, I can see him inside the lobby for a short period of time but then he disappears. On his screen there is only the “ranked overview” with “cancel” and “search for ranked” button. No way to keep him stay in the lobby. Is there any known issue or help to fix it?