Very interesting concept of a game! Really like the idea of being lost in a dungeon with no cell service, even the song fit in perfectly before the ominous music hits in.
One thing I wasn't particularly fond of was that you moved and jumped with your character using the mouse, would it maybe be easier with the arrow keys or WASD? :D
I don't know if you've heard of Game Development World Championship before (gdwc2019) but it's a competition for indie game developers where they can submit their games and it's free! It's great if you want some more visibility for the game and it only takes a couple of minutes to join :)