Second monitor dimmed down

After playing the beta, i have met this issue that i cannot manage to fix in any way. I play on a big monitor while my laptop, which is running the game, functions as the second monitor. While playing the beta, the second monitor( the one without the game) dimmed down, and stayed that way since then. I cannot manager to bright it up. Uninstalling the game did not fix the problem. The only temporary solution is turning on the laptop while hdmi is unplugged and then plugging it in. Is there a fix?