Your neutral light switch probably needs replacing...The part is $18.00 and they are on the 4th revision. I replaced mine two years ago and am still "good to go".
Five minutes to do yourself if you don't want to bring it in for warranty work.
Check the wires on the switch itself for integrity. Some have removed and cleaned the neutral safety switch itself then reinstalled without further problems. I just cheated and changed the switch because they had a bad batch reported back in the day so I cut to the chase and changed mine. No more flickering.