Been there, done that.
The tumblers are sticking. You need to remove the entire ignition lock assembly. In my case I got another one from a junkyard and moved tublers from one lock to another.
You might get lucky and be able to clean it. For me, a good cleaning only seemed to help for about a week. Kept a can of WD-40, but that’s only a temp fix. WD-40 seems to attract dirt/dust.
There are Youtube videos on this. Its not too hard.
Also, I believe the dealer has a kit to replace. The kit comes with a selection of tumblers. You stick your old key into the new ignition and make sure the tumblers line up perfectly (and move smoothly).