Treating Customers unfairly

I received a call from a miway consultant offering me a life cover policy, after she gave me all the information concerning the product, I agreed to taking the policy. During the call, all relevant questions including health and lifestyle questions were asked, I did answer all of them, even disclosed that I was diagnosed with Rheumatoid arthritis, at this point of the call,the consultant informed me that she was calling their underwriter to verify the condition that I had just disclosed, indeed the underwriter did ask me again about the condition, which I did again comfirm that i was diagnosed with it. The underwriter didn't say much, but the call went on after that with only me and the consultant who confirmed to me that I did quality for cover even took my banking details, I agreed to a deduction date and the premium. She told me a policy schedule would be sent to me in a few days time, indeed after two days or so I received it via email. A week later I received a call from a different consultant who said unfortunately they will no longer be offering me the life cover that I had agreed to take because I had disclosed that I had Rheumatoid arthritis, I couldn't and still don't understand why is it that I was told that my application was successful in the first place. It feels like I was misled and given false hope. I am so disappointed by the lack of professionalism and bad service that I received from this company.