If you bought the items within the last 30 days you can open a return request with ebay,choosing items as described for a refund,see here https://www.ebay.co.uk/help/buying/returns-refunds/returning-item?id=4041
The seller should send you a prepaid return label and refund you within 3 days of getting the items back.If they don't you can escalate the case to ebay.
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