After weeks of having my Mercari account locked, I’ve finally managed to verify my account. Every time I tried, I kept getting this Error 4400 saying something was vaguely wrong with my ID photo.
After numerous failures using my zairyu card, I randomly tried my MyNumber card and it didn’t give the error 4400 — but was later rejected for not being right document. That’s when I realized their document scanning AI expected the photo to be where MyNumber puts it rather than where the zairyu card has it! So I put my zairyu card on my MyNumber card, shifted just enough to show the photo, and it worked. An hour later I had a verified account.
So, if you are struggling with 4400 error, just put a photo to the left of your zairyu card.
by Spiritual-Anybody-88