I have had my Ring Doorbell 2 installed for about two months. It was ringing fine, but today it started saying “install cover”. The cover has not been removed, and I am unsure what to do. I have tried unscrewing the faceplate and reseating it, but nothing changes. Other internet forums say something about installing a small plastic shim over a cover sensor, but I cannot locate where this sensor would be. Any help would be approciated!