What's the point in gap cover? Do not use Stratum!!

I took out Gap cover through a company I worked for. Stratum sent in a rep who told us which policy to take and what to complete on the form. I believed they were giving me the best policy. This was in 2016. I have paid my premium every month. I have since had a knee injury where I need to pay in R 2,420.00 for an MRI scan as my medical aid has run out form the hospital and dotors' appointments. I am now told that the policy I am on does not cover co-payments (which is what the rep told me to take out). Upon looking at the policies, it shows if I paid just R 20.00 more a month, I would be covered for all of this. How can you reject my claim when your rep assisted me in taking out the policy. She clearly does not know how to explain the policies or does not know your products on offer. I am very disappointed in the service I have received. I will be looking for another provider as I feel I am paying for nothing all this time. My dad is with Stratum and I have told him he needs to look as well to go to another provider because I wouldn't want him to get stuck seeing as he is retired and would really suffer financially. As gap cover is always explained, it covers co payments and shortfalls. Well Stratum does NOT!!