Dahua thermal image showing grey screen with flashing blue and red circles

s300bee

n3wb
Aug 28, 2025
1
0
england
Hi
I have a new to me Dahua Thermal Hybrid Speed Done Camera TPC-SD2221. The thermal camera is displaying a blank grey screen with flashing blue and red circles moving around the screen. I really don't know anything about these cameras, any ideas?! Thanks