What is the reason for the return? This might determine the best way to handle it. Generally, a buyer wishing to make a return will open a request through eBay, specify the reason, and then the seller accept/refuse based on that.
The reason specified will determine who is responsible for the return shipping cost, and the process from that point.
If you can provide a little more info, myself or others on here can guide you on what to do next.
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