******** Debit Order

I have a contract with telkom which is coming/came to an end. I submitted the cancellation request over a month ago on the telkom app. So beginning of this month i didn't receive the data and so I assumed my contract finally got cancelled. Today however I awake to find that my account was debited R428.37 late last night out of the blue for no reason. I really would appreciate some answers ASAP, since I don't owe telkom anything and my debit is end of the month not on the 15th.