DIAGNOSIS Insufficient airflow or a dirty temperature probe causing the controller to misread and underfeed pellets.
FIX Clean the RTD probe. Let the grill cool, unplug it, and carefully wipe the probe (left side wall) with a soft cloth and a bit of rubbing alcohol. Built-up grease insulates it and gives false low readings.
IF THAT DIDN'T WORK Check for airflow restriction. Ensure the grease drain tube at the back isn't kinked or blocked. Verify the drip tray and heat baffle are correctly seated and not warped, which can disrupt the convection flow.
HEADS UP Ambient temperature and wind matter. In cold or windy conditions, the grill will struggle to reach high temps. Using a thermal blanket or moving it to a sheltered spot can help.