This reaction is often confused for aggression, but there are some ways to distinguish it from other forms of aggression. (pethelpful.com)
As mentioned for other forms of aggression, use commands to teach your dog obedience. (dog-health-guide.org)
If you think you are the only one dealing with biting behavior or other forms of aggression when you touch your dog's collar, rest assured you are not alone. (cuteness.com)