Switched my cell contract to a data contract

<p>I recently took up a data contract with Vodacom through the call centre. Instead of using the new sim that was sent with the modem they changed my existing Vodacom contract to the data contract. </p> <p> </p> <p>The store at Tyegr Valley then refused to assist saying I must go through the call centre, who seem even less willing to help. </p> <p> </p> <p>I have no idea what to do and who to contact to resolve this matter!</p>