Double Debit

Good day I have a contract with intellicell. August and September they decided to double debit my account. I have phoned them many times to pay back the money, they said it will take 5-7 working days well the complaint was made, 2-Oct 2017 Today is 12 -Oct 2017. Still no payment from them back in to my account. I have phoned 5 Times today 12 Oct 2017 and still no one is phoning me back or solving my problem. I have to wait according to them, but they do not wait to get their money. So end of October they will double debit again since no one is getting back to me or solving my problem.