Well...
The game looks really good. The overall atmosphere feels dense, it has creepy vibes, reminded me a lot of "Cry Of Fear" and the sound design - superb. But...the main gameplay of it is just purely directionless and I died at least 25 times trying to find all the keys, cutting all the necessary corners to avoid the main antagonist, which can literally go through walls and through ventilation system.
If you are making a game with a constant threat, you should add a safe point for the player for them to hide, wait out the killer/monster and then continue on with the task. If you constantly make the player run from the antagonist and have 0 safe points, that will create a plateau and the player will just give up and exit the game. I wonder why didn't you implement the safe points within the ventilation? It would make more sense to hide in the vents or move through them, while the antagonist is chasing you, but they would never be able to catch you while you are there. A missed opportunity, in my opinion. And what was up with the phone? Not explained, sadly.
Overall, I think with a small update and more backstory to what the player has to do in the game can create a better experience.
Good luck.
Edit: This is not the first game I played, which was made by you and in the previous game you had the same exact issue - balance. Seems to me, the last time it didn't work out so well. So, I hope you consider the changes.