Need some help......

[Loudmouth LS1]

Hey guys, haven't used efilive in years, used the V1 cable back in the day to tune my 99 camaro race car and it was awesome!!! I bought a delete kit for my 2012 DMax Sierra. I did all the mechanical work and went to drop the tune in and having a problem. The delete kit came with a v2 efilive handheld tuner. I can see the tune when I scroll down that it says is supposed to be the tune in the instructions, but it doesnt say program. When I click on it, I get error $0502. Deleted dpf and cat, put in egr block off plates and installed 5 position switch, but cant do anything since the tune wont load. Anybody able to help me fix this? I reached out to the tuner, they claimed they would send me instructions how to fix, its bee. Almost 4 hours since and reached out multiple times since and I still have nothing. I really need to get the truck running, need it for work tomorrow, did everything on my day off today and of course the part that should take 2 mins is screwing me up now! Thanks so much for any help.