Have you tried the log out/log in dance? The site does sometimes seem to get caught betwixt and between.
I did finally get it to acknowledge what I wanted, to find seven, or so, of the same product ... lol. After removing the extras, I was able to add the rest of what I wanted, then cash-out.
Of course, then I realize two things I bought, I’d bought before ... lol ... so had to put in a refund request. The second one this weekend. But all-in-all, I bought a bunch of stuff I’ve been wanting.
I just wish this site would get it’s head out ... you know? I spend a lot of money here ... I’d like to think that’s worth having stress-free purchases.