Cannot stop door locking hazard lights.

Neighbor called to ask if I meant to have my hazard lights blinking.
Went outside with key fob and pressed the unlock function. But it would not work. Had to use the slide-out emergency key to open the door.
Car started fine but on turning the car off I noticed the small pinpoint red light next to the remote lock function was blinking and that it was automatically locking and relocking the doors setting off the hazard lights as it did so.
Again, the unlock function would not work and I used the emergency slide-out key to get back in. Opened and closed all the doors but the blinking red light on the fob plus out-of-control flashing of lights (and clicking of locks) continued.
I've wrapped the fob in aluminum foil to stop the remote signals from continuing to cause flashing lights.
Anyone have any idea what the underlying problem is and how to solve it?