Ring Spotlight Cam Pro doesn’t work at night

I have a major problem with my spotlight cam pro. My doorbell and camera are linked, so when the doorbell picks up motion the camera light comes on and records - except it doesn’t at night, rendering it pointless because I don’t need a light during the day. I phoned customer services, they did a firmware upgrade - didn’t work. I phoned again, they sent a replacement. That arrived today, I set it up and have the same issue. It’s not a Wi-Fi problem as it records linked events fine during the day. It’s not a doorbell issue as I have one of the original spotlight cams also linked and that works perfectly fine day and night. Ring - can you sort this out?