Faulty i

[yammaha_2009]

Hi please can you help

on a faulty radiator that I have purchased has only been on the car 10 months and only covers 1500 miles seller is not responding 

order number is 08-13025-63408

[**peaseblossom**]

I'm afraid it's too late to do anything via ebay or your payment provider.   If the value makes it worthwhile try the small claims court, now called money claim online:
https://www.moneyclaim.gov.uk/web/mcol/welcome

Also contact Trading Standards if it's a UK business seller.    You could tell the seller you intend doing both those things and see if that makes them respond.