My card (linked to bank account, real fiat debit card) was denied due to billing address, I was willing to ship to a friend in US what I ordered.
Many thanks for you hint, I'll look it up, let's also see other options if anyone else know
I bought an item in US (through Amazon) and I use my PayPal wallet for purchase, I'm not from America I lived in Asia, it took me less than a month to get my items, and when I receive it all works fine to me. I don't know why does your card gets denied, they will accept VISA, MASTERCARD, BANCNET or CIRRUS card. There's a thing called Dropshipping too, you will put that dropshipping address instead of yours and then from dropshipper's address to your home address, but I think additional fee might be needed. Check shopify for more info.