If it's an older one (not sure about the new ones), there is a magnet glued into the top of each latch pin. One of mine came loose, and would occasionally cause that symptom. All I have to do is push down on the tip of the latch pin to re-seat the magnet, and all's well. Next time I'm in there (and remember it) I need to dab a little epoxy or put a drop of superglue on it.
The alignment of the reed switch can also be a little touchy. You can adjust the position of the switch for more reliable operation. One of mine needed about 1/8" of adjustment right after I bought it.
RV-12 # 222 N980KM "Screamin' Canary" (bought flying)
Fisher Celebrity (under construction)
Previous RV-7 project (sold)