Poor service and no response to complaints

I have been having problems with my wifi modem since the day I joined MWeb. In the beginning the modem was defective and had to be exchanged. Then I had an enquiry on my account and I sent an email on the 16th of April 2015. The reference number for the email was ***. To this day, almost 1 month later I've had no response to this email. On 3 May 2015 my modem suddenly stopped working and the message was that my 5 GB of data was finished although my online account showed I had only used 10%. I phoned and spoke to Noel who informed me he couldn't help me but he would lodge a compliant. I also said that I wanted to cancel my contract with MWeb due to the extremely poor service I have received. My reference number for this call was ***. Again I am still waiting for any response from MWeb. This is the worst service I have had from any service provider ever.