[Ranked Season 7] Ranks not properly reset?

I am unable to invite or get invited to a ranked solo/duo game from a friend of mine. The error message says, that we are too far apart in rank to play together. Our profiles say that we are both unranked and by the time that happened, neither him nor I had played a single placement match. In season 6, we were indeed too far apart in rank to play (Plat 4 and Dia 5), so it appears as if the rank was reset on the profile page, but wasn't reset properly in the system? We both restarted our clients and we are both using the new client. Anyone else encountered that problem or can reproduce it? I will try it with another person, who I wouldn't have been able to play with last season either as soon as they're online.

Update: I can reproduce the bug with another guy, who ranked Diamond 4 last season. Same error message. I can reproduce the bug with someone, who ranked Silver 4 last season. Same error message. The error message didn't occur when I tried to invite a former Gold player.

Greetings, Izussa