MacBook Pro not restarting

My 13" 2017 MacBook Pro with Touch Bar on Mac OS High Sierra 10.13.6 cannot be turned off/restarted properly.

Every time I need to turn it off or to restart it, for example when installing certain updates, the screen turns black, but the cursor remains visible, and the trackpad and the Touch Bar remain usable.

I tried booting in safe mode and shutting the computer off from there, but it still has the same issue.

Today I wanted to install Mac OS Mojave, but since it requires some restarts, I couldn't update.

Do you know any solution to this issue?