I don’t know why exactly I was unblocked, but here’s what I did:
- I tried to fill out my profile as much as possible (avatar, name, billing address, tax information, etc.).
- I linked a card and made a few purchases (a couple of SNES-style JRPG asset packs).
- I changed my password.
- I enabled two-factor authentication.
- I linked my GitHub and social media accounts.
- I contacted support (they didn’t reply).
- I wrote in this thread (including my support ticket numbers), and a kind moderator, No Time To Play, forwarded my situation to support again.
- In my messages to support, I explained that I had taken care of security (new password, two-factor authentication, linked GitHub) and also mentioned that my IP address might “jump” due to technical specifics of my internet connection (which is true, though I won’t go into details here — but I described everything honestly to support).
I don’t know which of these steps actually helped, but maybe this will help someone else.