UNSATISFACTORY CUSTOMER CARE

I purchased a rice cooker online which I collected at Roodepoort branch. The rice cooker is faulty, it burns the foods all the time. I phoned the branch on 9 November and I was requested to email them the rice cooker invoice and the silver sticker details found underneath the rice cooker, which I did. I have done 2 follow ups via email and to date I have not had any feedback. If I call them they put me on hold for over 20 mins and cut off the call. I need urgent assistance.