Game crashes when call on Games.Leaderboards.show(

[NathanFitchett]

So I have it setup in the beginning like so to start up the sign in process which works fine and signs in without error:

                            Games.initialize();
            Games.start();
            Games.promptUserToSignInOnStartup(true);
            Games.beginUserInitiatedSignIn(); 

The problem I am having is in my Game over Screen Function When I call on show leaderboards like so:

Games.Leaderboards.show("CgkItMj7kJEQEAIQff");

It automatically crashes. I'm not sure exactly What i need to do in order to fix this issue am I missing something? Do I need to add more? Please any help would be appreciated