amana plga30aw heat comes but later out

Dryer has always good until lately. Whenever you start the drying cycle all is well. the ignitor comes on as the flame comes. After about 5 minutes the flame goes (normal) but then when the ignitor comes on again the flame will not light. It I start the dry cycle again all is well again for 5 minutes the problem repeats. I have cleaned the exhaust nothing helps

amana provide no assistance or parts list