Put in payment info a dozen times, don't matter. It want a billing address (despite how it's a pdf).
Put in address, then it says I have no payment info. Put in payment info, now needs billing address. Repeat endlessly.
So I put in a billing address 1st, despite how that option isn't normally there on the first go. Then put in payment info again without clicking to confirm the address, and despite how it was right there already, and suddenly it was able to buy things.
You owe me aspirin...