ERROR: _block_literal_generic or _block_invoke - ios

Question

I'm having an issue finding the source of this crash in my iOS app which has a core data model using iPhone app i am not able to login URl. I am using same code on iOS 7 its working but now I am trying to work on iOS 8.2.Have issue for _block_literal_generic
Block point is below As well check screen shot for block Error:---
[[NetwokManager sharedInstance] loginRequestEmail:userEmail andPassword:userPassword WithResponse:^(id responseObject, NSError *error) { if (!error) {
}
Using code is below:
-(void)sendLoginRequest
{
NSString *userEmail = [[NSUserDefaults standardUserDefaults] objectForKey:#"emailKey"];
NSString *userPassword = [[NSUserDefaults standardUserDefaults] objectForKey:#"passwordKey"];
NSLog(#"Email %#", userEmail);
NSLog(#"Password %#", userPassword);
NSString *mobileNo = [SCUserProfile currentUser].callerid;
NSLog(#"CallerID %#", mobileNo);
[[NetwokManager sharedInstance] loginRequestEmail:userEmail andPassword:userPassword WithResponse:^(id responseObject, NSError *error) {
if (!error) {
NSLog(#"responseString = %#", responseObject);
if (responseObject == nil)
{
NSLog(#"No data from server");
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:#"Error"
message:#"No data downloaded from server!"
delegate:nil
cancelButtonTitle:#"OK"
otherButtonTitles: nil];
[alertView show];
}
NSDictionary *resposneDict = (NSDictionary*)responseObject;
NSString *success = [resposneDict valueForKey:#"success"];
if ([success isEqual:#"Authentication Failed"])
{
[self showAlertViewWithMessage:#"Authentication Failed"];
// [self sendLogoutRequest];
[[C2CallAppDelegate appDelegate] logoutUser];
}
else if ([success intValue] == 1)
{
amobilePayUserID = [resposneDict valueForKey:#"user_id"];
[[NSUserDefaults standardUserDefaults] setValue:amobilePayUserID forKey:#"AMobilePay_User_ID"];
NSLog(#"User Id is:= %#",amobilePayUserID);
}
else if ([success intValue] == 0)
{
//[self sendRegistrationRequest];
// [self sendLogoutRequest];
// [[C2CallAppDelegate appDelegate] logoutUser];
}
else
{
[self showAlertViewWithMessage:#"Unable to login AmobilePay"];
}
} else {
[self showAlertViewWithMessage:[error localizedDescription]];
}
}];
}

Answer 1

Crash in unknown region 2015-04-30 09:56:18.390 AmobipayMerchant[337:60b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[MOC2CallEvent costs]: unrecognized selector sent to instance 0x16ef2dd0'
Somewhere in the code, you called costs to an instance of MOC2CallEvent. MOC2CallEvent has no method or property costs, so of course it will crash.