Everything in my Scene is DELETED!

I need help!
a couple days ago I created a game, and when I loaded it up, everything in the heirarchy and on the scene was GONE! Every other time I saved and loaded the game, it worked flawlessly!

I followed tutorials!
Some suggested deleting all meta files, while others suggested changing the unity interface script… BUT NONE OF THESE WORKED!!
Please assist.

it happened to me too!!
I found a solution:
DO NOT SHUT DOWN YOUR SYSTEM IF UNITY EDITOR OR UNITY HUB IS OpEN!!!
if you do unity will not be able to save the last scene data thus deleting all the data from scene and making everything new on startup!!

@JamesEatsSocks