Nairtime keeping on taking our money

There is no way to get hold of them their contact number is not even their number, they deducted twice from my bank and from there on other amounts of R10.00 and today got a sms now I owe them R12.45 and they will list me with the credit bureau, all the complaints what is happening that all have the same issue. How can Vodacom sign up with them? There is not even an email address for them.