I don't have a a 396T but I do have a 996xt. I have added, changed, renumbered things many times. No, many MANY times and have discovered that occasionally this will happen for whatever the reason. You can spend a lot of time trying this, and checking that (I've done all that) and scratching your head trying to figure it out since it was working just a little while ago or you can just go fix yourself a cup of coffee and reprogram the thing fully - It only takes a few minutes, doesn't wear the scanner out, and is FREE and has always corrected my issues. I suspect the programming can get corrupted in the scanner with multiple partial uploads, but who knows.