My gas dryer runs for ten minutes the flame cut off and doesnt turn back on its the second dryer .?

we got another dryer after compleatly rebuilding the first one and the same problem. pse&g repaired a gas valve outside after calling them and still same problem.called them again they came out test the pressure and its good. it does get gas vent is cleaned out. i also plugged it into another outlet and disconnected the vent and still the same problem what could it be ...... please please help us