Overcharging

I was previously on my parents medical aid which was discovery and had vitality, I joined planet fitness with the vitality benifit, in September 2014 I joined my own medial aid on discovery and vitality. I notified planet fitness that I had changed to my own as above and they told me I didn't need to do anything as discovery would pick it up automatically and my benifit would be transferred to the new medical aid. I was charged the normal benifit rate up until January 2015. In Feb 2015 I was charged the full amount and I can't ates vitality to let them know that there was a problem and requested a refund. I was told I would get a call back within 7 working days to rectify and refund. 2 weeks past and no call. I phoned discovery back and they told me there was a backlog and they would attend to it. I asked to speak to the manager who told me he would escalate the problem. As of today 01 March 2015 I have again been charged the full amount from planet fitness and received an email from them that my gym benifit has been removed. I demand a full refund for these 2 months and for this to be sorted out immediately.