GKTurnBasedMatchmakerViewController disabled "Send Game" when recipients are set

When I run the following code, the Matchmaker view is populated with me (local player) and my opponent (correct picture and friendly name). however, the "Send Game" button is disabled. I assume that recipients is set correctly.

There are errors from loadPlayersForIdentifiers .

  GKMatchRequest *request = [[GKMatchRequest alloc] init];
  request.minPlayers = 2;
  request.maxPlayers = 2;
  request.defaultNumberOfPlayers = 2;
  
  request.inviteMessage = @"Testing";

  [GKPlayer loadPlayersForIdentifiers:@[ playerID ]
                withCompletionHandler:^(NSArray<GKPlayer *> *_Nullable players,
                                        NSError *_Nullable error) {
                  if (error) {
                    NSLog(@"Error loading player: %@", error);
                  } else if (players.count > 0) {
                    request.recipients = players;

                    GKTurnBasedMatchmakerViewController *mmvc =
                        [[GKTurnBasedMatchmakerViewController alloc]
                            initWithMatchRequest:request];
                    mmvc.turnBasedMatchmakerDelegate = self;
                    mmvc.showExistingMatches = NO;

                    [self presentViewController:mmvc
                                       animated:YES
                                     completion:nil];
                  }
                }];

If I remove the opponent, and then re-add them manually, the "Send Game" button is enabled.