BIS cancelled with upgrade, still billing me!

I upgraded November 2015. The day I upgraded (phoned a customer service rep from the website) they asked me if I wanted to cancel BIS and I said YES please for I do not have a BB anymore. So the first month my bill was higher than normal but I did except it for the first month of a new contract is usually more. This month it was the same again!!!! I checked my invoice and guess what.....I''m still being charged for BIS!!! I spoke to someone at vodacom on Monday over the phone (***) and he promised me that it will be sorted. He also said I would get an sms with a reference number that my query has been logged.....I have not yet received anything. This is not my mistake and I want a refund and BIS cancelled with immediate effect. My husband has the same problem, also did not receive a sms to say his query has been logged. We want this sorted asap please....