how to get insurnce company to pay out insurance policy

took out a life insurance policy for my dad in oct of 2006. He passed away 1 month before they could contest the policy. When I purchased the policy the agent that did the paper checked off a box that said that my father did not have an internal diease which he knew he did. he was told about the lung cancer, due my ignorance and not reading over the policy, I did not know he checked that box until we had to use the policy to bury my dad. My dad passed away 1 month the two year period was up and now they want to contest the policy. they have been giving us the run around saying that they cannot get his medical records from the hospital. Please give us some advice of what we should do.


Thank You