Long-term superhost of several years? Sorry to say, but you're most likely being ghosted - the longer you're on the platform, and the more over-saturated your market, the more frequent and prolonged the ghostings can become. Those who discover that their listings have gone missing from the searches, and who make enough noise about it with Airbnb, will usually have the situation (temporarily) rectified by CX (who will often initially try to deny there's a problem with the listing at all)
Not a whole lot you can do about it unfortunately, except call in and try to get it sorted, as soon as it happens, every time it happens. Or in extreme cases, closing down your account and starting over may be the only viable option. Yes, I know that sounds absolutely nuts - particularly for those with long proven track records and hundreds of excellent reviews - but it's the reality, sadly. Best of luck! Hope you manage to get back in the game soon.