why my cell did't change when i receive signal?

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:bust_in_silhouette: Asked By potatobanana

tower scene

 var sell_done_cell =1

    func _ready() -> void:
        emit_signal("sell",sell_done_cell)

world scene
my current cell id=4

   func _on_tower1_pressed() -> void:
    
        var tower_instance = tower_1.instance()
        tower_instance.global_position = map_to_world(last_cell) + cell_size/2
        tower_instance.connect("sell",self,"_on_sell_done")

    func _on_sell_done(sell):
        set_cellv(last_cell,sell)
        print(sell)

last_cell  last click position vector2 , sell = 1

but did’t change