Mlm0910

I have a 2021 GMC Sierra 1500 AT4 3.0 Duramax. I recently lost one of the key fobs provided when I purchased the vehicle. I ordered a replacement, cleared the existing fobs, then attempted to reprogram the existing key fob and the new fob. I successfully cleared the existing key and got through all the steps of reprogramming up to the point where the display says ready for Remote 1. The truck does not recognize that a remote is present to program and now I have no working remotes. The truck has been towed to a dealership where they are running into the same issue. I accidentally set the alarm off during my reprogramming attempt and had to unhook the battery. Is it possible this could have fried the BCM or has anyone else run into a similar issue.