Disgusting service

I am having the most terrible experience with vodacom and it's service from their call centre agents. I called in to query abt my billing...the agent said it would be resolved...i then get debited more than my monthly billing and according to their agents...i can log it but there is nothing customer care can do...so my question is...how does a query get actioned at vodacom? They send no notifications with regards to my account. Their agents are rude! I am disgusted with the service from vodacom!!!!???