Confused by your post. First this is not eBay support it is a seller discussion forum so eBay will never see your request to "close my eBay account" if that is what you are trying to do. Not sure if you are referring to sending offers as a buyer or a seller. As a seller you have nothing listed so I am assuming you are saying you cannot send offers as a buyer.
If that is the case there are a lot of pieces to being able to do that. Are you getting any type of error message and if so what does it say. Do the sellers you are trying to send the offers to ship to the UK? Do you have a payment method on file with eBay since in some instances eBay is requiring the buyer to provide payment information in advance of placing an offer or a bid.
A bit more information would be helpful.
