MTN DOESN'T CANCEL CONTRACTS EVEN THOUGH THE NUMBER DOESN'T EXIST?!

MTN South Africa please explain how you have an "ACTIVE ACCOUNT" when it was cancelled 9 years ago... when you call the number it even says "THE NUMBER YOU HAVE DIALED IS NOT AVAILABLE ON THE MTN NETWORK"... When I call your "efficient teams" all I hear is "THERE IS NO SUCH ACCOUNT"... BUT SUDDENLY LEGAL DEPARTMENT SAYS IT IS ACTIVE???? I look forward to your response on this