HI Perveloper =)
Buy button is not visible for users. Because of this users cant buy game. Game is deleted? If game is not deleted - in forum dedicated itch.io i found possible solution. If developer uncheck checkbox "Hide this file & prevent from being downloaded" on game page, buy button is returned. Link where i foun this information: https://itch.io/t/138490/buy-button-is-gone-
I hope that helped)))
P.S. Sorry for my potato english ;)