MTN Misrepresentation

In November 2017 l was approached by MTN agent by the name of Themba Ncube who offered me an online cellphone upgrade l indicated that l was interested in Samsung galaxy S8 he informed me that they were running a special if I take that phone l will get R250 voucher which l can spend on any Samsung products. I never got that voucher I send him emails and he ignored them. During our conversation he also indicated that their special includes free 3 months subscription which means l will not pay the contract for the first 3months , my account Will be credited with R1800 which will cover that 3 months as l am going to be paying R599 per month. I made sure that l get that in writing in a form of email from Mr Ncube , to my surprise l got an invoice that l must pay R599 l called MTN and spoke to one Dineo Maome who told me that on her side the only thing that appears is a debit order scheduled to go off on the 15 of January l then sent her the email from Mr Ncube , she sent an email to him saying he must assist me. As usual Mr Ncube ignored that email. The number in question is ********** 449