Discovery insure useless.

I have been with discovery since 2014 and I am really disappointed. Discovery has been robbing me of my vitality cash back. Firstly in June I was supposed to receive R543 rands and I got paid 200. I called and complained then they reimbursed me in July but then my July Cash back was supposed to be R345 and I got paid R100. I really wondering if this is the way discovery robs people for good driving. I called the call centre and the agent I spoke to said he has logged in my complain and I did not get any feedback. I called again and the agent I spoke to said that he will call me back but he never did and he made me hold for more than 15 mins before he said he will call me back. I actually used to think that discovery is the best insurance company but i really disappointed and on top of that they way they treat their clients. This thing should have been sorted out plus I HV wasted my airtime calling them. it's really frustrating. This must be sorted.