Top I ordered from Ebay has arrived and is dirty - best way to handle this?

[Arcticantics]

Ordered a top from Ebay. It was described as Used but in very good condition

It has yellow stains under the armpits!

I paid £22 for it so not as though it was dirt cheap either.

What is the best way to handle this?

Thanks

Message seller and send photo of the top and say you want a refund as item not as described