Do you see the "You own this game" text and download button at the very top of the page?
yeah. Checked it recently and it's letting me download the latest update but for some reason every now and then when a new update drops it won't let me download it. Guess that's just something on itch's sid
It depends on the button, the one at the top checks if you already payed, the other one don't, that's just how itch works.
