double payment to one account

I manually pay my cellphone account inside the bank before the actual debit order goes off. And in the time it's done the payment reflects on their side so no debit orders go off my bank account. On Monday i get debited by cellc for the account i have already paid and now i have to fight and run around trying to get my own money back ,I have been doing this for the past 4 years. This is highly ********* that it takes a giant company 7 seconds to take money from my bank account but takes 7 days to receive my own money back. And constantly when I contact customer care regarding my refund i get told "don't worry you will be called in 24hrs, because when i was called i was busy working and couldn't get to my phone to take the call it has been almost a week and no response no feedback. And now i have been inconvenienced as i have to compromise as the money i had was taken. I have a family and other responsibilities that need attention, the reason i have been managing my account in this manner.