I’ll try and keep it short.

I am a Canadian seller who has sold an item to a buyer in the USA. The customer has complaints about the function of the product. His complaints are not valid, they are technically nonsensical. Furthermore I have a no returns policy for cross-border sales clearly displayed on my site. The downside to me simply honoring his request for refund would the lost (2x)shipping cost + potential that I will have to pay duties when the item reenters the country.

If I deny the request for return/refund, I run the risk of him initiating a chargeback. I understand that he can claim a chargeback based on the item being unacceptable.

1. If he is successful in his hypothetical chargeback, he would keep the product and also receive the money?

2. Is there any chance of the card issuer siding with me since I can easily prove the item was received, or is the alleged defect sufficient for his chargeback to be successful?

Thanks for taking the time to read and for any insight.