False information increasing premium and failure to correct this from Vodacom

A lady from Vodacom phoned me to upgrade my son's Vodacom cell phone contract. She mislead me over the phone and gave me false information about payment etc. I reported this to Vodacom after which they did an adjustment, but the premium is still not the same as before and I was promised a refund for the months I paid too much. This review has not happened. I have contacted them numerous times and the customer care personnel are just ignoring my e-mails. Unacceptable service and taking up my time because a Vodacom employee blatantly **** to me.