Issue with front locker locks

Investigate whether it's the lock barrel or the catch itself (from the symptom sounds more likely) is faulty.  If the lock barrels are OK, I believe they can be removed and fitted into new plastic catches (which are cheaper then the complete assembly) and you won't then have any extra keys.

My guess....

The lock is a D shape and is supposed to fit a D in the lid. The D in the lid has maybe worn to a round hole, so nothing to locate the lock.

If it is the lock, often the actual lock barrel can be released by pressing a sprung button when the key is in the lock - which avoids the need for different keys.