Billing for a device or airtime I am not receiving

Vodacom has done it again, I had to call a billion times to fight, argue and be told that the incident has been closed, this was without a doubt, *********** as I did not receive feedback. A new incident was created and finally received notification on Saturday that I will be credited, however instead of receiving money, Vodacom bills me for the same error as last month. When will this end. I am getting frustrated here. And it becomes a hassle to get the money back