Refusal to pay for treatment.

Despite paying a huge amount of money to Bonitas, Denis refuses to pay for my dental treatment. I haven't claimed anything from Denis in 4 years. Now all I get is that I have to pay for the dentist and the dentures as well. Techno speak all the time, there is no reason why they will no pay for this particular treatment, but they can pay for alternative treatments. It makes no sense. Never again and I'm canceling.