Input is null ?

What would make Input null ?

Code :

func _process(delta):
	if Input.is_action_pressed("Left"):
		pass

Error :
Invalid Call. Nonexistent function 'is_action_pressed' in base 'Nil'.
Obs: In debug view, Input is null ...

I figure out :

@export_group("Input")

This bug got me again, changing to the following fix it :

@export_group("Inputs")