In the first instance, please take a look at our sizing and fitting blog post here to see if you can adjust the item to fit on your own If you are still having trouble, please reach out to us via Instagram, Facebook (@twiggytags) or to contact@twiggytags.co.uk with your order number, your dog's measurements, photos showing how the item isn't fitting and any information about your dog that may help us (breed/mix and weight) so we can check the fit/adjustment ourselves, and arrange a return if we need to!