[igortessele]

My game changes from normal to legendary difficulty. I don't know how to switch back to normal

[blackpirate]

My game changes from normal to legendary difficulty. I don't know how to switch back to normal

Restart the game and set it to "Normal". Then load the current save again. The problem, however, is that the values in the world remain where you are. What world and what chapter are you in?

[VV0ll3]

My game changes from normal to legendary difficulty. I don't know how to switch back to normal

The problem is that at some point you must have started another game with legend difficulty. The difficulty is then reset in your other savegame for the next world (Island) that you enter. You can do this again, but have to load a savegame of the previous world to reset the current one.