In defence of Itch.io some time ago when I requested a pay out - itch.io sent me an email to ask me to update my tax information and requested that I reply to their email once it was updated so they could process the payment. It seems in your case, you didn't receive that email, while they were waiting for you to reply. Based on forum comments that's happening a lot.
Perhaps itch.io needs an online system where people can enter their ticket numbers and see if there are any follow-up requests.