It may be the international aspect of the transaction. I have a son, daughter-in-law and grand children in the UK. For birthdays, Christmas and other similar events, I send Amazon UK gift cards. But whatever US credit card I have tried to use to pay for them, I have been informed that the charge was "refused" and now know I have to call the card company to authorize a transfer overseas. I'd guess that is what you are experiencing from your location to the US. If you need to buy something in the US in the future with a UK-sourced credit card, call the credit card company FIRST to authorize an ioverseas charge of the appropriate amount (taking into account of course, exchange rates. Not many here are familiar with pounds or euros.) Better luck next time -- but I agree, Nikon's customer service practices leave a lot to be desired.
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