Failure to correctly advise

I had contacted Old Mutual in 2012 to take out a life policy, at the time I was not very fami**** with all the different offerings in a policy and trusted the financial adviser entrusted to me with all the dealings and add ons in a policy . Last year I wanted to increase my life cover and had emailed Old mutual several times to contact me to help in this regard but no response. I then managed to contact an old mutual adviser who then brought to my attention that my initial policy did not include the illness benefit which is something that is offered to all new policy holders, I told him that I was not aware of this and also that I thought this was all inclusive in my policy as since 2012 I have broadened my knowledge. I have now been diagnosed with Lupus and guess what I cannot get any benefits cos of your employees incompetence. I am left with a huge hospital bill and ongoing treatment and medication costs that if I were correctly informed I would have not be in this predicament. I have filled in the contact form on the old mutual site as well from my online profile in my portfolio but still no response from Old mutual. What do I do in this instance?