Wrongly data billed

We were billed for Data in December about R3800 on new years eve when the phone wasn't even used, I've been fighting Vodacom for this, we ended up paying the amount as we need to use our lines, Aurther Jantjies contacted me regarding the bill 2 months later and left a voice mail for me explaining that we are due a credit but will email me details on how to reach him, till today no email was received and we have spend numerous hours on the phone trying to get this sorted but still nothing. up to today Vodacom has not paid me my credit back that is owed to me and they just keep expecting me to pay my bill as invoiced. When we threaten to not pay until this is sorted we get told our lines will be blocked. This is the most pathetic service I have received form any company. Vodacom just takes money but when owed money they don't contact you back to try to resolve the issue. Vodacom also Listed me on ITC for a non payment for less than a month due to them still investigating the matter.