contract cancellation

my contract reached its expiry of 24months and i've requested a cancellation of contract on the 2nd Sep on their website, end of Sep they debited and now i received an invoice for Oct with that subscription i've requested a cancellation on, i called the call center and to my surprise they said i didn't make any request while i followed the steps from logging-in, managing account, cancel service, selected the account i wanted to cancel and followed the wizard and even attached my ID and got to the last confirmation page and i get this ****!. am so ****ed cause their coverage is poor and i never skipped any single payment and i will never take any product from Telkom ever again!.