Doorbell Pro flashing white

I just received a refurbished unit from Amazon. I'm installing it on my back door. I already have one on my front door so I know the installation process. My new doorbell is flashing a white light at the bottom RIGHT. Assuming there are 4 "light zones" mine are currently solid white at the top left and right, blinking lower right, and no light at the bottom left. Can anyone tell me what this means?