Black screen on HeroBook Plus

yesterday while I was taking an online course via video, the screen of my HeroBook Plus went black, as if someone had turned a switch off. Even though I didn’t see any images, I continued to hear the audio of the video I was watching.

I tried turning the notebook off and on again several times, even though it restarted, the screen continued to be black, preventing me from taking any action.

The last operation done before the screen went black was to decrease the video playback speed.

Can anyone give me information on how to fix it?
Thank you