NSUbiquitousKeyValueStoreDidChangeExternallyNotification not fired - ios

Question

i just released my app and realized that NSUbiquitousKeyValueStoreDidChangeExternallyNotification is not fired.
I need it that it is fired the first time a user open the app to register him (and check if it was already a user before).
The problem is that, if the notification isn't fired, then my app will be stuck.
I'm using key-value and it's properly setted in Xcode
Now, with my iphone, with developer profile, everything works great.
With a distribution profile, it does not.
I already have a production profile with icloud enabled (and app id with icloud enabled too).
In my app, this two parameters,even in the app store version, are fine:
_currentiCloudToken = [[NSFileManager defaultManager] ubiquityIdentityToken];
_myUbiquityContainer = [[NSFileManager defaultManager] URLForUbiquityContainerIdentifier: nil];
Here's my code:
- (id)initWithCloudStore:(NSUbiquitousKeyValueStore *) store {
if ((self = [super init])) {
_iCloudStore = store;
_currentiCloudToken = [[NSFileManager defaultManager] ubiquityIdentityToken];
_myUbiquityContainer = [[NSFileManager defaultManager] URLForUbiquityContainerIdentifier: nil];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(storeDidChange:)
name:NSUbiquitousKeyValueStoreDidChangeExternallyNotification
object:_iCloudStore];
}
return self;
}
-(BOOL) iCloudIsEnabled {
if(_currentiCloudToken && _myUbiquityContainer != nil) return TRUE;
else return FALSE;
}
-(void) sync {
if([_iCloudStore synchronize]) NSLog(#"iCloud Sync OK");
}
-(void) storeDidChange:(NSNotification*)notification {
NSString *iCloudUUID = [_iCloudStore objectForKey:userUUIDKey];
if(iCloudUUID != nil) {
NSLog(#"iCloud UUID present with value %#",iCloudUUID);
//[[iCloudHelper sharedInstance] removeObjectForKey:userUUIDKey];
// sostituisco uuid locale con quello di icloud
[[NSUserDefaults standardUserDefaults] setObject:iCloudUUID forKey:userUUIDKey];
[[NSUserDefaults standardUserDefaults] synchronize];
} else {
// salvo uuid in iCloud
NSLog(#"UUID not present on iCloud");
[_iCloudStore setObject:[self createNewUUID] forKey:userUUIDKey];
}
int reason = [[[notification userInfo] objectForKey:NSUbiquitousKeyValueStoreChangeReasonKey] intValue];
if(reason == NSUbiquitousKeyValueStoreInitialSyncChange) {
NSLog(#"This was the initial sync");
}
[[NSNotificationCenter defaultCenter] postNotificationName:#"iCloudDone" object:nil];
}
What I'm missing?