You weren't supposed to print it literally, You repeated my typo's :)
Look at the function You used in documentation. It says it returns ERROR when something goes wrong. It says, that there are 3 possible errors when scene does not reload - no current scene defined, impossible to instantiate scene, impossible to get packed scene. You need to use print to get and read this error. SOmething like this :
If get_tree().reload_current_scene() == 1:
print("error nr 1")
elif get_tree().reload_current_scene() == 2:
print("error nr 2")
and so You will know why it does not work