You are not paying the buyer protection fee.

It's been explained numerous times, the buyer makes an offer which is the maximum they are willing to pay, eBay then take the buyer protection fee from this buyers payment and pass the rest on to the seller.So Why do you think you are paying the fee?

In your case the buyer is willing to pay £830, eBay take the buyer protection fee from this leaving you £817

For once eBay are clear when they show in your offer message how much the buyer offer is and how much the seller will receive.