Trippy movie that left audiences confused. Told audience members not to spoil the movie

I’m trying to remember this film where the characters are experiencing surreal situations until they wake up. There are clues while they are dreaming that lead them to waking up.
It’s discovered the people wake up in a room with others who are also experiencing the same weird dreams. The ending turns out to be a game set up by rich people who bet on which people escape the simulation.
The survivors are given a lot of money and it turns out some people go back into the game for more money. The more games they win, the more they can move up the social ladder. If they win enough they can join the elite class.

The movie has a point where it reveals the secret and it tells audience members not to spoil the movie for others.