Just purchased a 440 Tailgate, second attempt cooking today. Had to finish chicken last night with direct heat as the meat does not seem to be cooking on top, at all. Attempting to smoke at 225. Top of meat seem to not be cooking at all, no color change, appears raw. Is this an issue with the convection? It seems to be in good working order and temps read correct. Temp gauge on lid never reads as high as it should either. 1.5-2 hours for chicken breast that I had to finish over direct heat. Please help!