Billing Issue

In the month of may i get a bill from telkom telling me they are gonna put off my Internet because of money owed to them. I found out from the person responsible paying the bill for the Internet that they did not pay for the previous 2 months. I phone telkom and tell them that it is fine they can switch off my Internet and i will gladly pay the bill at the end of the month in full, everything that is owed. End of may comes and i pay the full sum and they switch on my Internet again. Now 1 month after i have paid the sum due they tell me that i need to pay for the month of may as well. But my Internet was off , i did not use it at all. I phone the a day or 2 ago and ask what is the issue because I'm not going to pay for something i did not use . They keep telling me that my net is gonna be switched off in the next week if the bill is not paid. But i keep asking them why i should pay for something that was not suppose to billed at all , but they give me vague answers . I spoke to 3 different billing agents on different occasions and to 2 different supervisors as well . I could not get a straight answer as to why I have to pay for a month that I did not use their product and service