Hi,
it looks like the IR filter is stuck. It normally switches in and out based on ambiant light and is used in combination with the IR LEDs to provide you with night vision. You can hear the filter engaging.
if a reset does not work, you can try trapping the doorbell to see if it will release the filter. Or in a dark room, or at night, shine a touch or light briefly into the lens to see if you can "shock " a filter switch. You should hear the filter as it engages.