Endless issues with customs

Hi, I've had endless issues with Fedex dealing with customs. My company purchased a computer part from Ebay. It arrived at customs on the 21st of May. It's been stuck there for nearly 2 months now. We've been asked to supply bank statements confirming the item purchase. Which we did. Now we're being told to pay a penalty fee of R500 because the item price on the invoice ($17) doesn't match the amount reflecting on the bank statement we sent to Fedex. I have clearly explained to Fedex that the amount we've paid included Fed ex shipping fees of $43.55 - total amount paid = $60.55 (which would you believe, is the exactly amount reflecting on the invoice. This Ebay purchase order was sent to Fedex last month already. Can someone from management please intervene here so we can have the part delivered to us before Christmas or do I actually need to have this shipped back to the seller and have it delivered via a "reliable" source like the post office? (the irony…)