Why doesn't the cross key fit in?

Safety lock thinks, this kind of situation has three possibilities: 

1, it is not when you are in the key to pull back to the position, lead to keyhole misplaced (most keys are worthy of, with the number of times many, with smaller than the original, cause the lock hole is bigger than the original space, so any one direction are likely to pull out the key).

2, that is, there is a quality problem with the safety lock itself.

The lock was opened by thieves with tools.