Vodacom refusal to cancel my contract

i have been trying to cancel my contract since its expiring date in October, but to date the contract is still active and now they have suspended my network service for non payment as if i'm at fault... their consultants are not even willing to listen..

WHEN I CALL TO CANCEL THEY KEEP ON TELLING ME THAT MY CONTRACT IS ON THE M2 ( OLD SYSTEM) IS IS FOREVER OFF-LINE.

this is part of the contract : " After the Initial Period / Renewal Period (twenty four months) this Agreement will automatically continue on a month to month basis subject to any changes which we have notified you of unless you or Vodacom terminate it on at least 20 (twenty) business days written notice."