Is there a locksmith in the house?

A couple of years ago, there was a recall on some locks put in RVs for this reason. Do a little research and see if yours was one that was recalled.

No signs of thief, nothing stolen,
BUT... tampered with it was, per my request. Bear with me.

A year ago I lost all the keys. Village mechanic came up and made duplicates without taking the locks out. His method of work was not much different from that of a lock-picker: inserting the blank into lock and hitting it with a pair of pliers from left and right. Thieves do the same with a lock-picker tool, only hitting it with a forward motion. This way he got impressions on the blank telling him where to remove the metal, went to the shop and made me the keys.

He could've damaged something. Is it possible to replace just the barrels in deadbolt and striker? without buying $$$ same lock that is indeed very low security. The whole door is 1" block foam with fiberglass sheets on both sides, one could kick it in with a heavy boot.

Ok, on a standard lock cylinder there is one "pin" which is NOT operated by the key.. This may be the 1st or the last tumbler, its job is to lock the cylinder in place.

If a thief uses a slide hammer to pop the lock it will be destroyed in the process

If the door is locked.. Look at the "other end" of the cylinder (The end that goes into the lock) there should be some kind f paul or pin there that moves somethignat the back of the latch.. You need to move that to unlock the door

Beyond that. Visit a locksmith for a new cylinder and lock inspection.

It sounds like the disc tumbler which keeps the plug in the lock got loose. I would look at replacing the handle to be safe, as there have been a couple recalls in the past few years for something similar happening.

In your absence, has anything been stolen from or moved around inside your RV? If your lock is like many others, the tumblers hold the lock cylinder together. If someone has monkeyed with the lock, that could be the issue. Or it could be worn out. Lack of lubrication, freezing temperatures, dirt, or UNKNOWN could cause your symptoms. If there is no evidence of tampering or damage and it works fine after you put the lock barrel back in, you are probably fine but be suspicious. On a scale of 1 to 10 (10 being safest) those locks are about 2 as far as safety/security goes. My RV has a residential style deadbolt lock in addition to the factory lock.

Chum lee