I got a problem when analyzing my code below :

```
NSDate *formatterDate = [inputFormatter dateFromString:smBook.time_limit];
formatterDate = [formatterDate initWithTimeInterval:1*24*60*60 sinceDate:formatterDate];

```

The message is : Incorrect decrement of the reference count of an object that is not owned at this point by the caller .

Can anyone tell me the reason why ?