That does look confusing.
I wouldn't know whether to expect 3 months or 12 months warranty.
However, warranties are entirely between you and the seller. Ebay give you 30 days to return an item after purchase using the Ebay Money Back Guarantee.
I would advise contacting Citizens Advice Bureau to see what 'next steps' they can suggest. They can usually only offer any practical help if you bought from a UK business seller.
"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)