Stop debitting my account

Vodacom needs to stop debiting my bank account! I received notification that R178.26 was debited off my account on the 27/08/2015 by Vodacom and I have no idea what this debit was for, but of course the amount was returned because it was debited off my dormant account. I then got another notification R117.22 taken off 03/09/2015 which was returned once again.<br> My question is where did they get my account number from and why are they debiting my account when I can guarantee that I do not have any contract or subscription with them. <br> I now have bank charges for bounced debit orders of which could have been avoided. <br> May I have one of your consultants call me because I cannot seem to get a direct line to the department that is responsible for this as it needs to stop.