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[jermykyle1987]

I believe that the buyer of my item is trying to get a refund for a item they say they haven't received but I very sur they have and are trying to get a refund and keep my item. I would like some help in how I can resolve this problem 

[**peaseblossom**]

eBay will go by the postal tracking.   You can only be sure the buyer has received the item if the tracking shows delivery, in which case they would lose a "not received" claim.

If the tracking does not show delivery, assuming you used Simple Delivery ebay will issue the refund when the buyer opens a case, and you keep the payment.

[jermykyle1987]

So I will lose a sell and my item?

[papso22]

Assuming you didn’t use simple delivery and you don't have tracking showing delivery, you have no seller protection. 

You will therefore have to refund and will lose the item as well.

Without evidence of delivery you cannot be sure they received it.