Rika austroflamm insert will not reignite

The last few days my rika insert will not reignite. Since this is my first season i have been trying different pellets.Platinum Fires (i liked them) Powerhouse hardwood (ok but a lot more ash )Right now i am burning Turman hardwood pellets,which burn awesome and have extremely low ash.(my preference so far) still have Barefoot to try
I have it set up with the thermostat pellet controller
In the evening it is at temperature (72) this temp keeps the entire house comfortable , then in the evening at bedtime I set it back to (68) this allows the bedrooms to be comfortable about (62-64)
Normally the house cools then as the stat reaches about 65-66 it reignites. The last few Days the pellets drop into the burn pot but do not ignite.if I empty the burn pot of pellets and cycle it off then back on it ignites and runs perfectly.
I have been very diligent about cleaning
Am I missing something , any help or suggestions will be greatly appreciated