Question about Surface Dock 2 - 415395

Saluti together, I've had a problem since today, and everything was running until the lunch break. When I went back to work afterwards, only 1 monitor was still running. Before that I had 2 (Dell P2719H) and once the display from the Surface Pro 7. The one screen always stays black and says it has no signal via HDMI. But according to the device manager, 2 monitors are connected. Does anyone have any ideas what I can do? or has the Surface Dock 2 already gone bye-bye after 1 week?