Do you have the tuner (I.e. SCT)? I find it odd that he would tell you to go to AutoZone to clear a code. The tuner should be able to do that.
Before you get any tune from someone else, make sure you still have the factory tune file either in an email from your tuner or on your device tuner.
Before you get any tune from someone else, make sure you still have the factory tune file either in an email from your tuner or on your device tuner.