iOS : No Notification Received from Facebook App Request

I have to integrate app request on my app but it doesn't seem to work. I searched about it and I can't find a clear answer. Some replies from the reports said that the request can be found in Facebook App Center but I didn't receive any request and also, no notification was received.

I'm using Facebook SDK for iOS v3.8 to send the request. There's no error and there's a request, it was always successful but still no notification.

Here is the code I'm using to send the request.

- (void)sendAppInvite:(NSString *)message {
    NSMutableDictionary *params = [NSMutableDictionary dictionaryWithObjectsAndKeys:@"app_non_users", @"filters", nil];

    [FBWebDialogs presentRequestsDialogModallyWithSession:[FBSession activeSession] message:message title:nil parameters:params handler:^(FBWebDialogResult result, NSURL *resultURL, NSError *error) {
        if (error) {
            // Case A: Error launching the dialog
            NSLog(@"Error on app invite.");
        } else {
            if (result == FBWebDialogResultDialogNotCompleted) {
                // Case B: User clicked the "x" icon
                NSLog(@"User canceled app invite");
            } else {
                // Case C: Dialog shown and the user clicks Cancel or Share
                NSDictionary *urlParams = [self parseURLParams:[resultURL query]];
                if (![urlParams valueForKey:@"request"]) {
                    // User clicked the Cancel button
                    NSLog(@"User canceled app invite");
                } else {
                    // User clicked the Send button
                    NSString *postID = [urlParams valueForKey:@"request"];
                    NSLog(@"Request successful: %@", postID);
                }
            }
        }
    }];
}

I also tried to build the sample app from Facebook, I sent an invite. Still, no notification and no request from the app center.

Is there something that I'm doing wrong? Also, is there a bug from Facebook Request?

Thanks!

Only apps that are actually on facebook.com can use the Notifications API. Note this is different than "app requests". In other words, you can't get your app to post a notification in the top right corner where the globe is.