I have only one friend that's not showing up on my board. She all of a sudden disappeared!

My friend suddenly can't see me too, although I can see her just fine - and apparently I'm the only one missing in her list. She can't see that I was the one that sent her lives (even though the lives appear, my requests no longer appear, and the lives I send don't have a picture or a name of the player that sent them), she can't see me at the start of levels, ranking list or anything on the game. This problem suddenly appeared one day ago, we've tried the reset, log off-log in, restarting the phone, the app is up to date, cleared the cache, everything.. it doesn't work.

I don't have facebook, so we've always been friends through the King account for years. We have also tried adding one another again through the game (on a computer), but King says we are already friends - which is true on my phone, but no longer on hers. We both have Androids, by the way.

Anything else we can do? Has anyone been able to solve this problem?

Thanks for any help!