Farmville2 - can't invite friends?

[flubba]

Sadly addicted to Farmville2 but I don't spend real money on it, so need a friend. The only RL friend I know who plays it has only joined FB recently and I don't seem to be able to add her as she doesn't come up in my list of friends. Any ideas?

Maybe she blocked the app

No, she's definitely playing and I'm on her list??

I mean I've been invited by her and she can see me and visit me, but I can't see her at all!