Family Sharing: Can't accept invite

[MeanPJs TTV]

I'm trying to setup my mom with a game I have on my Library.
I sent her an invite which she received. It says she has a pending invite. When I try to accept it it says it must be accepted in the Steam App, fair enough
I go into the Steam App and accept the update. A dialog comes up asking if I want to confirm, I click confirm. Dialog disappears, no error message, but Steam says the invite is still pending.
Help!

[123]

same problem

[MeanPJs TTV]

So I managed to figure out the problem I was having.
The Steam app on the phone was out of date. I went into the Play Store and found 30 something apps needed updating on my mom's phone.
After updating it worked fine.