Issue with AddPlayersToMatch on iOS 8

I'm working a matchmaking screen with U3DXT and I have an issue with AddPlayersToMatch but only on iOS8.

Here's what I'm trying to do:

1. Player A do a matchmaking.FindMatch().

2. Player B do a matchmaking.FindMatch().

3. When the 2 players are connected, Player A do matchmaking.AddPlayersToMatch().

4. After 10 seconds Player A leave the match with match.Disconnect() and matchmaking.Cancel().

5. Then Player A is stuck in a state where he will never be able to do a matchmaking.FindMatch() again. (He always receive an error code 13: GKErrorMatchRequestInvalid)

As I say, the same flow is working correctly on iOS 7.

Anyone know why the Player A can get stuck in that state, or how to fix his state ?

Thanks