Possibly at the point where you actually bothered to print, sign, and mail a physical letter (by registered mail so you can prove it). At that point, there's n

Possibly at the point where you actually bothered to print, sign, and mail a physical letter (by registered mail so you can prove it). At that point, there's no need to state it, go straight for the chargeback and attach a copy of the cancellation letter and registered mail receipt.