i am purchased solar powerbank30000mah but that was not described ebey rejecting for replacement

[ak1853]

iam ordered a solar power bank 30000mah on 29-11-16 rececived on 5-12-16 on 7-12-16 iam compliened to seller through ebay  on 7-12,9-12,12-12,15-12,19-12-16 respectively  on 17-12-2016 the seller(gowinall2014)as per his reply to me he was arranged return courier for my item but even today 31-12-16 nobody not came to me for my item on 20-12-16 iam raised a complient to ebay regarding this . they were rejected my case. the seller and ebay both were not responding to my mails so who will replce my item as the powerbank was defective so i copliened to customer care by phone on 26-12-2016 complient no ;TS/023071 ,as per customer care executive it will be solved in 72 hours but failed in this matter from 7-12-2016 i am sending mails to seller through ebay they know every thing but thry were rejecting for replacement of my ordered one paisapay id is44212642616 item no;232041909327 ebay guarantee id; 2562124 in this case seller mr gowinall2014(WILLIAM ALEXANDER) worst seller at least 2000 times called to him by phone(04040273789) but he never responds to this , i think this is purely harrashment to the buyer  i dont know how ebay supports this type of sellers,not only this the seller given a mail that on 5-12-2016 item was shipped but in original iam received the item on 5-12-2016 so blently ebay beleiving sellers only not the buyers