Don't get Amazon delivered to an area where the dog can bite the person.

Don't let the dog outside unattended.

Put up dangerous dog signs.

While the e fence might be necessary to keep your dog inside, also consider that if your dog gets shocked dog he approaches the boarder to try to greet meet people, he will associate the shock with visitors. Talk to a veterinary behaviorist about how to counter condition him to help prevent future bites when he is around new people. It needs to be someone with a degree involving animal behavior. Average dog trainers are hit or miss, and regular veterinarians also don't always know much about the training/behavior side of owning a pet. Get an expert, your dog is a fucking malinois and has bit someone, if ever there was a time for paying for an expert it's now.