This error might occured becuse the nitrogen has gone overrange and the signal was to high for the machine to cope with. This might be caused by to much sample weight or during analyses and it generated a blockage in the post combustion or combustion tube. If using the robotic arm check the hole i at the end of the gripper arm.
you could also try a fine leak just to make sure aswell.
Just repeat the analysis on a much lower wieght and use your standard for a guide on how much weight.