Same issue here..last night to my horror I discovered my IB had been turned off when my listings were suddenly showing up as request to book and also not showing with the lB icon in search results. I have had to decline a few enquiries recently who were people just using Airbnb to enquire about renting houses in my area for working on the local ski fields, not actually making an Airbnb booking (I realise now maybe I should have just pre-approved them and left the dates open, argh). I also declined one reservation request who had no reviews and no profile information (didn't feel comfortable with that, at least make an effort when you have no reviews!). And finally, one legit cancellation a few weeks ago from someone who didn't answer any of my preset questions, told me nothing about himself or his trip, and didn't answer any of my messages for the whole day, so I cancelled him.
Wrote a message to Airbnb and got the same response others are getting...inane things like "your listings have instant booking turned on"...yeah thanks, but it's clearly not working!! Either they have terrible IT or they are literally bullying hosts into accepting more guests for their own profit, even though the whole concept is based on safely letting a stranger stay in your home. I don't have much hope I'll get it back on soon and I'm really pissed off as we're in ski season now and school holidays are soon. Definitely putting my house on some other hosting platforms asap.