I know of lot of forum members have had issues with the fuel door not unlocking or sticking. In my case, the fuel door pops open randomly. This recently happened at a car wash and you can imagine the outcome. The air blowers at the end of the car wash blew the fuel door right off the hinge. Luckily, I got the fuel door back and it wasn't in too bad a shape; I was able to reattach it.
The last time I parked the car I also caught the fuel door unlocked. I pushed it in so it was flush and locked the car. So until I replace the parts, I have to lock the car twice to make sure the fuel door doesn't pop open when I go through the car wash.
Never had an issue whatsoever with mines and wonder if it's random, relegated to a certain production run, brought about through various usage conditions or something else. At any rate, great information.