Turns out that the transaction was canceled. The invoice was there, the PayPal account had a notification saying “You authorized a payment of...” but when I contacted Tindie support, they said that the transaction was canceled.
When I tried to order again, same thing happened, but this time I noticed the message “Your transaction was canceled...”. The culprit was the internet security SW that opened PayPal in a separate, protected window. Somehow Tindie and PayPal couldn’t talk to each other anymore. I had to turn off protection to place the order, which defeated the purpose of using an internet security SW.
Anyway, once I did that, the transaction went through and the nano VNA is on its way.