This is an IR FHD 24 mpix model V51 firmware V2.0  updated 2020.12.16, 16x digital zoom 1080p camera.  I don't know what I did with the orignial manual but after considerable digging I did find it online, and it always talks about the IR mode and the IR lamp turning on and off together when you press the OK button.  This has always worked in the past.  I thought I remembered seeing a lightbulb icon appear on the screen when I switched to IR mode, but I don't see that happening now.  It definitely goes to IR mode and the IR shutter moves away, but the IR lamp does not turn on, so the image is really dark.  I bought it around april 2021 so I realize it's well out of any warranty.  I ordered it from Amazon but not from your storefront.  When the camera is off, looking at the lamp, the left of the three LEDs is visibly darker, so i suppose its possible one of the LEDs burned out somehow.  (I thougt all three looked equally white before)  I could probably replace the LEDs if that's the problem, if I knew how to safely disassemble it.  I can send pictures of the lamp and of the screen if that would help.