Problem with Remote Keyless Entry and all door locks and lock switches, including automatic door unlock when vehicle is put into ‘Park’
If Lock on key fob is pressed once, only the rear right door locks. All other door locks are left unlocked and can be opened with no alarm sounding.
If Lock on key fob is pressed twice, horn beeps but still only the right rear door locks. However, if the other 3 unlocked doors are opened the horn sounds a continuous alarm until you push ‘Unlock’ on the key fob.
Pressing lock on the keyfob only locks the right rear door. Pressing unlock on the keyfob only unlocks the right rear door.
All doors can be manually locked by pushing down the lock button on each individual door.
If driver enters by unlocking only driver door with key in keyhole, the only way to relock that driver door from inside is to push down the lock button.
The power lock/unlock buttons on the inside of both front doors will only lock and unlock the right rear door.
When vehicle is started, driven, and then put back into Park, the right rear door automatically unlocks. No other door that was manually locked unlocks. Can only unlock them by pulling up on the lock buttons.
Is the cause of this a setting on the vehicle? A faulty fuse? A faulty relay? Faulty actuators? Or another electrical problem?

Door actuators are a pain. My CRV now only locks manually(11 yrs old) and my Frontier only opens on the right side with the key fob(10 yrs. Old). Typically there is 1 main actuator, drivers door.

I doubt it's the actuators, especially if all three doors started to malfunction at the same time. But I've learned never to say never, and maybe some electrical gremlin blew out three of them. If it was a bad fuse the whole system wouldn't work, but as a quick check look at the owners manual and it will show fuse locations. Check for door locks and check the fuse. There may be a settings function depending on the model(again check the owners manual), but this limited to when the doors lock/unlock, not to program one specific door. The door lock system on GM cars is pretty complex, and is controlled by a number of computer modules and relays, such as the driver and passenger door modules, lock/unlock relays, and body control module. The diagnostic chart shows 13 steps to check the front doors and 32 for the rear. If you know about cars you can do the tests, though it requires a GM service manual and door panel removal. For the work involved take it to a dealer or a qualified independent garage and have it tested.