I change the difficulty but the world always goes to journey mode, I've even tried to configure it directly in the folder but it doesn't work

tiene que borrar todos losdatos y luego reinstalar con la nueva configuracion

For terraria vanilla:
https://lemehost.com/hosting/127/terraria+vanilla

• Stop server
• In control panel visit Settings, change world name and difficulty
• Start server

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Execute command in console
(Valid modes: normal, expert, master, journey, creative)
Example

worldmode master