What if you return an item to the seller and he does not refund your money and he won't contact you

[wooden_flower]

If you opened a return request, eBay will make sure that the refund is issued within 2 business days of when tracking shows delivery to the seller.

If you did not open a return, eBay can not help you get a refund.

If you have tracking that shows delivery to the seller, call your credit card issuer. Ask them to open a dispute for a return with no refund.