********** debits going off my account

I did not have any vodacom contract and out of the blue I get an sms from with a stop order debit going off my account. Upon querying this would vodacom the consultant could not pick up anything on their side. I had to phone the bank to put an immediate stop. Only to see the bank reversed the amount another debit went off my account again but with a different reference number. This is ********** how the hell did vodacom not do background and verification checks. Up till now no one at vodacom has contacted me.