Good morning

I open this discussion in openly confessing I sent an incorrect order to someone, which should have been sent to another buyer. Even after profusely apologising to this person, offering a refund on postage and Express Posting the correct item to them, the person was incredibly difficult in communicating with in order to get the incorrect item back, and when I asked them to send back the item COD all communication stopped.

My fault, I get it, but...

This person still hasn't posted back the incorrect item, has received the correct item, and now says I haven't a leg to stand on in regards to getting the item back (was incredibly rude in their final communication when I stated I would put the matter to the Resolution Centre). Why am I not protected against people like this, who expect to keep the incorrect item along with their purchased item. It goes against the fundamental principle of a contract/transaction! The person that I have sold the item to now doesn't get the item and I have to provide a full refund. And on top of it I get my first negative feedback and have to wear it for attemping to get the item back.

Any comments? I understand I basically have to wear it this time and learn from the mistake.