Faulty 24-70 from eBay

Hi folks,

I’ve just bought (yesterday) a Nikon z6ii with a 24-70 f/4 kit Lens form eBay for just over £1200.

They both arrived yesterday in great cosmetic condition and the body only has around 12k clicks on the shutter.

I attached the lens to find out that it does not auto-focus (no such issue stated on the eBay listing). Just arrived home after taking it to my local camera shop to find that the Lens is at fault (not the body).

I’ve messaged the eBay seller who seems to be willing to work with me on this issue.

I don’t particularly want to send the entire kit back as the body is a steal for the price I got it but do I ask for a partial refund of the cost of a second hand Lens and offer to ship the Len’s back to the seller?

Any advice would be greatly appreciated.