https://www.paypal.com/c2/smarthelp/article/how-do-i-use-my-unionpay-card-to-mak...
thanks, i send message to paypal, maybe it's their issue. btw, i can pay for itch.io
paypal told me my account is normal, i don't know the reason. i use debit card, no credit card.
i can buy other assets from itch.io, paypel doesn't let me to pay for starbird using debit card, but can pay for itcho.io.
I'm not sure what else we can do. If you send an email to StarbirdResources@tutanota.com I can try to send the files to you directly.