Robot Kingdom & Paypal

[JJJ]

I have just attempted to purchase the Origin Bumblebee from Robot Kingdom (because all the scalpers on e-bay start at over $100, and from RK it will come to only ~$50 with their absurd postage), but I cannot pay for it.

RK's only payment method is Paypal, which isn't an issue - I use Paypal all the time (just last night, in fact). But every time I go through their checkout process, I briefly see the usual screen where I would confirm my address and then confirm payment, only to have it replaced by a screen telling me that I have no payment method linked to my Paypal account. Which is complete rubbish.

I have disabled all my script-and-ad-blocking, tried with multiple browsers on multiple machines, no change.

Any suggestions? Does anyone else have this problem with RK? Is it just that their web-shop is as borked as their postage options?