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Hello,
I've been playing with my friends on an smp and downloaded the world.
I deleted the server and made a new one, and uploaded the world (zip file)
It says that server was played in a newer version.
I had used PaperMC 1.18.1 both the times, though it doesn't work
Please respond quickly 
Are you sure you didn't use the world in a newer version?. You can't using the same world in an older version of minecraft. You can regenerate your world for now
You could have been using viaversion on the server through which you could join with an older version of minecraft. Regenerate your world or use it an newer version of minecraft to play on it
