Neither eBay nor PayPal get involved in warranty issues.
The eBay MBG which lasts for 30 days after receipt of the item but is not a warranty and relates to the item as received.
The PayPal MBG lasts for 180 days but again is not a warranty.
Any responsibility now rests with the seller directly.
Trading Standards or Citizens Advice may help you if the seller is a business seller.
If the seller is a private one, no warranty is implied
