With your locks, you can never be sure that the situation will always be under control. The key breaking at any time is something you can never predict in future. All you can do after it has happened is use professional help. Unfortunately a part of the key is blocked inside the lock when the key breaks. Even if you have multiple spare keys, you cannot use them. The broken part is to be removed first in order to make space for the spare key to get in and unlock the lock or start ignition of your car.
