@kaushal64...
Not sellers fault, its your fault. Seller has clearly mentioned "no warranty on the product" and you still bought it. You should understand immediately when seller mentions "no warranty" that it is a counterfeit product as Kingston offers 5 yrs warranty on pendrives.
Why blame ebay for it, ebay cannot go after every seller with a stick beating them so it is you the buyer who has to be vigilant.
File refund case with ebay ASAP and get your refund from ebay.
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