I used to order all the time and have it delivered to Border Services.
I do not recall ever having issues with address, although I cannot for the life of me remember now if I had to adjust. Maybe it is simply your credit card having a different level of security?
I used their website and ordered just as you normally would , however using the delivery address as Dunseith. Maybe try calling their help line? They might have a trick something like using the numbers from your postal code when you buy gas. I wish I could be more help but as I live five minutes from the border now it is a heck of a lot easier for me to grab the US only products