MTN the cheat

I had a MTN number for almost 10 years on prepaid.In January 2015 a sales consultant contacted me with regards to changing to contract she explain the package which seemed very good your receive R100 air time with a cell phone. I agreed to the contract the handset was delivered I receive my bill everything was going well.Currently I receive a bill of R1450 I contracted MTN customer care I waited on line for almost 45mins spoke to a consultant he advise it was for data usage I advise how could that be he explain something of google updates still don't understand.<br> I asked him to send me a statement with regards to my usage i provided my email but never receive nothing.I call again this time it was quicker I only waited 30mins but still did not receive a detail statement. MTN has really let me down