Don't wait on the seller responding, look to open a case of not received here in this link if you within 30 days of the estimated delivery date,https://www.ebay.co.uk/help/buying/returns-items-not-received-refunds-buyers/get-help-item-hasnt-arr...
The case can be escalated after 3 days to ebay if you get no refund,BUT the case would close if the seller provides postal tracking showing the item was delivered.
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