Making a game more engaging for new players?

Hello, I have recently released a game about a week ago and while the game was successful in getting new players who really liked the game at first. Recently new players have been leaving after a few minutes of play time. Since this is my first game I want to find out some techniques to make the game more engaging for new players who join.

If you want to see for yourself here is the game :

https://www.roblox.com/games/2073181918/Mining-Mountain-Server-Challenges

Thanks for any advice or feedback!