In general, @Hillary39, location in the search results is driven by activity. I see only 3 reviews for your lovely home, so the drop in the search results is related to that, not to Instant Book or not. I actually found your listing on the first page of the search by narrowing the price to under $600. When you first list, Air BNB gives it a boost in the search for a while to allow more exposure, then it is up to your activity to keep it up in the results.
If you want to get more business and reviews, you need to market your place. Some of us dropped our rate below the comparable listings for a time and then raised it as we gathered reviews. I don't know how your listing measures with other comparable ones. Good luck. You seem to be off to a great start!