near side door lock problem

came home from work today and noticed my door lock on the n/s is loose, i could pretty much pull it out with my hand :worried: i used the door in the morning and it was fine and there is no way someone could have tampered with it at work as its in our yard and the car has no marks on the paint or plastic handle not even a smudge on the dirt?

has anyone had this problem or something similar and how can i re fit it as the plastic surround has very minimal play now?