Cell C unable to explain cost on my account

I have unexplained costs on my account. After taking off from work (at my own expense) I visited the local store to resolve. They were friendly but could not assist and needed head office to assist. 5 days later and several attempts from the local store I was called back stating that they can not help me because head office does not want to help them. <br> <br> Where does this leave me now? Still every day R17.50 is taken from my account because of the inability of Cell C to communicate within their own structure and eventually the ability to answer my query and resolve my problem. <br> <br> All I need is for Cell C to do is to STOP this cost I did not approve to go off on my account. - Today still please.