ltz2011

Also code p2463

Hello. 2011 model. Have gotten "engine power is reduced" light. Scanner show codes P24A0 P0420 I tried dpf regeneration for several times and its dosent help. Its still soot. The temperature doesn't go over 300 Celsius +-. I cant know the exact number cuse i cant do regen and chack stat at the same time. What could be wrong? Also glow pluge number 2 and 6 are not ok,dont know if there is connection to the dpf problem. Thanks.