Hi, I'm experiencing the exact same issue with my game page as well.
My game 'MY MIKO' (https://david-the-coolest.itch.io/my-miko) has been unindexed from Search & Browse for nearly a month. I opened Ticket #396289 back in late August, but still haven't received any reply from support.
Hopefully a moderator or staff member can check both of our tickets soon!