You reach for the collar to move your dog, and they turn their head and growl. That warning is worth listening to. A grab may hurt if the neck or ears are sore, or it may predict that your dog will be pulled away from something they value. Don't punish the growl or try a faster grab next time.
If the reaction is new, if touching the neck or ears seems painful, or if the collar rubs, ask your veterinarian to check for a medical cause and review the equipment fit. If a bite has happened, use distance and barriers to keep people safe and seek qualified behavior help. Avoid having children handle the collar.
Give movement a different cue
When your dog is comfortable and away from the difficult scene, practice calling them toward you and rewarding generously. Use a gate to guide them into a safe room when needed rather than pulling by the collar. For essential lead attachment, invite them to come to the harness or lead, reward a brief touch, then release. Work toward clipping on in short, easy sessions.
If your vet clears handling and your dog remains relaxed, you can pair the sight of your hand approaching the collar with a treat, then a brief touch, then a gentle hold. Each step is separate. Let your dog move away between repetitions. Don't lure them into reach only to grab and restrain them, that makes your invitation unreliable.
A dog who comes over when you call has given you a better tool than a last-second collar grab. For difficult situations, ask a reward-based professional to build a plan that keeps that trust intact.
Sources: Dogs Trust: How to handle your dog. Dogs Trust: How to train your dog to wear a harness.