My iOS app uses Facebook for logging in, however my dev team recently decided to consolidate all our apps into one universal Facebook app with a common APP ID. So I went into my project and tried to change my FacebookAppID and URL Types to the right APP ID, but when I run the app and click on the login button, it redirects me to log into my old app on Facebook. I have absolutely no idea why this is happening, but here is what I have in my AppDelegate file:
/*
 Callback for session changes
*/
- (void)sessionStateChanged:(FBSession *)session
                  state:(FBSessionState) state
                  error:(NSError *)error
{
switch (state) {
    case FBSessionStateOpen:
        if (!error) {
            // We have a valid session
            NSLog(@"User session found");
        }
        break;
    case FBSessionStateClosed:
    case FBSessionStateClosedLoginFailed:
        [FBSession.activeSession closeAndClearTokenInformation];
        break;
    default:
        break;
}
[[NSNotificationCenter defaultCenter]
 postNotificationName:FBSessionStateChangedNotification
 object:session];
if (error) {
    UIAlertView *alertView = [[UIAlertView alloc]
                              initWithTitle:@"Error"
                              message:error.localizedDescription
                              delegate:nil
                              cancelButtonTitle:@"OK"
                              otherButtonTitles:nil];
    [alertView show];
    }
}
/*
 * Opens a Facebook session and optionally shows the login UX.
 */
- (BOOL)openSessionWithAllowLoginUI:(BOOL)allowLoginUI {
    NSArray *permissions = [[NSArray alloc] initWithObjects:
                        @"email",
                        @"user_games_activity",
                        @"user_location",
                        @"user_likes",
                        @"user_birthday",
                        nil];
return [FBSession openActiveSessionWithReadPermissions:permissions
                                          allowLoginUI:allowLoginUI
                                     completionHandler:^(FBSession *session,
                                                         FBSessionState state,
                                                         NSError *error) {
                                         [self sessionStateChanged:session
                                                             state:state
                                                             error:error];
                                     }];
}
/*
 * If we have a valid session at the time of openURL call, we handle
 * Facebook transitions by passing the url argument to handleOpenURL
 */
- (BOOL)application:(UIApplication *)application
        openURL:(NSURL *)url
  sourceApplication:(NSString *)sourceApplication
     annotation:(id)annotation {
    // attempt to extract a token from the url
    return [FBSession.activeSession handleOpenURL:url];
}
/*
 *Logout
 *
 */
- (void) closeSession {
    [FBSession.activeSession closeAndClearTokenInformation];
}