DEBITING MONEY FROM MY ACCOUNT FOR A CONTRACT I DO NOT HAVE

I made an application for a Telkom mobile device and an extra sim card for extra data, they only delivered the sim card. phone was never delivered on 13 May I cancelled the sim card and Mobile application, as they were taking too long to deliver device which I urgently needed. now Telkom is sending me Notice of Demand for owing them R360.00 for a device I do not have and a sim card that I cancelled with them. this is unacceptable. SOMEONE NEEDS TO SORT THIS OUT ASAP!!!!