Can't Accept

On the ‘Play’ screen, all the open games are greyed out as ‘Can’t Accept’ and the reason provided is ‘This is a ranked game and the difference is more than 9’. but it’s often not as I get this message for opponents with ranks close to mine.

What’s going on?

Look closer sometimes the message is actually Max rank is x

Yeah, sometimes that’s the case and I accept that.

It’s just that the usual message says I can’t play because my rank is more than plus or minus nine even though it isn’t…