Video Recording missing 15 minutes when a carrier claims they delivered a package

Ontrac claims to have delivered a package to my front door a few days ago but when I got home that day there was nothing to be found. Of course I reviewed my ring footage to back up my suspicion that the driver delivered to wrong address, but found that there is a 15-ish minute gap at the exact time of the delivery. I don’t understand how this happens or why I can’t see this missing 15 minutes but can someone help me with this? Ontrac refuses to help and the original vendor said to “look around the perimeter of the house” …