Bad service and money snichers

First the service is poor, the contact centre never answers the phone call also the watsapp agent takes 45min to respond to the massages. I paid my monthly payment and I keep on getting sms that my account is in arrears and I took time and send pop to their account .no response nothing. Today they have odesity to double my debit order.i am very angry. I need this rectified and my money paid back.