Car lock on my 2005 Chevy Aveo

I unlocked my car door this morning and drove to work. When I got to work and went to lock the door with the key the lock was so far in I could not do this. Any explanation as to what happened and how I get this repaired?

There is a C shaped clip, inside the door, which holds the lock in place. This clip has come off, or the lock body has broken. Any mechanic can remove the inside door panel, and repair the lock.