Stop the removal attempt when your dog stiffens or turns toward your hand. A nip is a safety signal, not an invitation to hold them more firmly. Check whether the harness catches fur, pulls over a sore ear or neck, or presses a tender spot. A vet should assess sudden sensitivity, pain or an injury.
For the next necessary walk, ask a qualified reward-based trainer or your vet to help choose safe gear and a removal plan. Do not leave unsuitable gear on unattended simply to avoid a difficult moment. Keep children and visitors away while it is handled. The everyday handler guide covers timing and choice in practice, but it cannot replace a bite-risk plan or a fit check.
When there is no deadline, practise the smaller parts separately: touch near the buckle, release the clasp, move the strap a little, and pause before the dog worries. Reward voluntary cooperation. If they move away, stop. A professional can help if the dog has already bitten, or if gear cannot be removed without force. Avoid repeating a full removal as a test.
Today, record which exact movement starts the reaction and call the vet about possible discomfort. The first success is taking pressure off both dog and person.
Sources: Dogs Trust on gradual harness training, Dogs Trust on choice-based handling, VCA on safety and management around aggression.