Intermittent Crash: - setObjectForKey: Object cannot be nil (key:ref_id)

Intermittent Crash: - setObjectForKey: Object cannot be nil.(key: ref_id)

ref_id object is string/number in the JSON response.

Same code works most of the time. But sometime it crashes (~less than 5%).

NSDictionary *udfDict = nil;

if (data) {

if ([data length] > 0) {

udfDict = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:&serializationError];

}

}

if (udfDict) {

NSString *transactionreason;

NSString *refId;

if (![CustomUtilities isEmptyOrNull:udfDict[@"ref_id"]]) {

refId = udfDict[@"ref_id"];

[dict setObject:refId forKey:@"ref_id"];

}

Concern: If its not able to downcast from number to string, the code should break all the time.But thats not the case.The crash is intermittent and only code breaks for ~5% occurances.