No notification shows on device(iphone or ipad) - ios

Question

We built an IOS game and now it's in the testing process. When we tried to test the Invite Friends via Facebook in game, we found that our request only showed up in two places: 1. The Home Reminders section in the upper right hand corner of the main news feed home on the desktop web version of Faceook.com. 2. The notification jewel on the desktop web version of Faceook.com.
The inviting request NEVER appeared in the notification jewel on device( iPhone or iPad). Does anybody know what we should do? Please help us. Thank you.
Here are the codes:
NSMutableDictionary* params = [NSMutableDictionary dictionaryWithObjectsAndKeys:
// Optional parameter for sending request directly to user
// with UID. If not specified, the MFS will be invoked
[NSString stringWithCString:s.c_str() encoding:NSASCIIStringEncoding], #"to",
// Give the action object request information
//#"send", #"action_type",
#"111111111111", #"app_id",
//#"2222222222222", _#"objectid",
nil];
[FBWebDialogs presentRequestsDialogModallyWithSession:nil message:[NSString stringWithCString:words.c_str() encoding:NSUTF8StringEncoding] title:nil parameters:params handler:
^(FBWebDialogResult result, NSURL *resultURL, NSError *error)
{
if(error)
{
// Error launching the dialog or sending the request.
NSLog(#"Error sending request.");
}
else
{
if(result == FBWebDialogResultDialogNotCompleted)
{
// User clicked the "x" icon
NSLog(#"User canceled request.");
}
else
{
// Handle the send request callback
if([[resultURL query] rangeOfString:#"request"].length == 0)
{
// User clicked the Cancel button
NSLog(#"User canceled request.");
}
else
{
// User clicked the Send button
//NSString *requestID = [urlParams valueForKey:#"request"];
//NSLog(#"Request ID: %#", requestID);
NSLog(#"User send request.");
}
}
}
}
];