Why is it so difficult to make a purchase on Nvidia Marketplace?

I'm just venting my frustration with the Nvidia Marketplace and hoping to get some tips. So, yesterday around 3:29pm, they dropped some 5090FE and I managed to add one to the cart. I spent next 30-40 mins trying to checkout. I kept getting "something went wrong". i tried different browsers, credit cards, mobile, and another pc, nothing worked. After about 30min, the page automatically refreshed to an empty cart. What kind of bs system is this that an item is removed from a cart because their system can't handle a surge in transactions?!

Normally, I wouldn't be this frustrated but this is the second time in the last 7 days this has happened. Like, wtf am I doing wrong? If their system can't handle multiple transaction at once, why not create a queue system to checkout or stagger drops to a rate manageable by their system? I wish there were other options at msrp or other high end options. Only cards available are the ridiculously priced. Any help provided will be greatly appreciated. Thanks for reading my rant. Have a good day!