You are too late to start a return with Ebay or Paypal - both allow 30 days only to return a faulty item.
If you bought from a UK business seller, it might be worth contacting Citizens Advice to see what 'next steps' they suggest.
Personally, if it is a UK business seller, I would write a letter and send it to their address explaining the issue and what I expect them to do.
"There are two ways to be fooled. One is to believe what isn't true; the other is to refuse to believe what is true.”
Søren Kierkegaard, Danish philosopher (1813 - 1855)