********** upgrade and continuous ******* billing

One of our company registered cellphone numbers was coming up with very high billing amounts and when queried, Vodacom stated that we had upgraded the account from 3g to a voice package. This was supposedly whilst we were closed in December 2014. Once investigated after a long period of time, over six months it was found that Vodacom had no paperwork to substantiate their claim and has asked us!! to move it to their ***** department who does not respond. <br> They are still billing on the incorrect package and have not refunded the incorrectly billed amounts. Going on nine months and tens of thousands of Rands.