Can someone please tell me what I am doing wrong. I have a 411 ecm from a 5.3, I am installing it on a 98 l31 5.7. I downloaded the file, bought 2 credits and started to flash it to the ecm. When I go to write to ecm it says that the vehicle isn't licensed but I just payed for and used two credits. Why would I have to buy more credits. I thought it only took 2 credits to flash a gm ecm.