As above, can be the micro-switch below the key, i had trouble like that years ago on another bike and i solved it by pushing the straw from a can of WD40 (GT85 will do it too)
right down into the assembly and giving it all a good dowsing then operate the lock quite a few times which can serve to clean the contacts in the switch, once the WD migrates
down there of course. Worth a try.