@Donn-And-Vicki0
Do you have the optional Instant Book settings turned ON?

We don't use Instant Book for the very reason you are posting here. Airbnb doesn't explain what "without incidents" or "negative reviews" mean? Is a negative review anything below 3stars? Is it 3stars in any category? What constitutes an "incident"?
Also, a guest can have a trip, but no reviews and will still be able to Instant Book.
Unfortunately, you can't cancel the stay without penalties. You CAN message the guess and put them on notice that you are aware of a previous, less than complimentary review, especially in the cleanliness category. You can ask if they could shed some light on that?