how to fix the lock or the key so it doesn’t stick in lock. only happens occasionally.
I could be a worn key, worn lock or a lock that needs to be cleaned and lubed.
Do not use WD40 in any lock ever! If you want to try cleaning it use a material made especially for locks or a zero residue cleaner.
Well I guess my very first suggestion is out. Maybe soap is safe? Motor oil?
go to the auto store. they sell a bottle of powdered graphite. you cut the tip of the bottle off (just a small hole) and squirt the graphite into the lock. you can keep the rest to do your household locks when needed too.
one note. the graphite is dirty, messy and gets all over. do it on a calm day, no wind, and hose off the car from what squirts out of the lock and down the side of the car.