Issues returning equipment

I canceled my internet service and that created a mess. The email that should have had the shipping label attached to it, did not have one. I just got the "sad to see you go" email. When calling customer support they where unable to send me an email with a label, due to my account already being closed. The business customer support side of things even tried to give it a shot with no luck. Also the store near me will not accept the return due to me already starting the return though the mail. So anyone have any idea how to resolve this so I don't have to buy a gateway I'm not going to use?