Help !!! What do I do next?

My father has an  Cancer policy to help offset the cost of him having cancer. I faxed the claim form to  Cancer Center in hopes that his doctor  would sign the policy stating my dad did have cancer. I called and spoke to the receptionist and she stated that the office had received the form and would get signature.  About two weeks had passed and I contacted the Cancer Center to see if the claim form had been signed and it had not.  About another month to six weeks had passed and I spoke to one of the Social Workers and she stated that it was on the doctor’s desk but still no signature.    My sister, Vicky contacted the social worker at the nursing home and asked her to see if she could get the signature. The social woker met with my sister within a few days and showed her two text messages from the Cancer Center that The doctor would not sign the claim form because I had been “confrontational”. I had not agreed with his treatment.

In order for my dad to start receiving benefits my family and I contacted a local doctor to sign off on the cancer policy.  

To resolve the problem, my family wanted to meet with the hospital and we would wanted a sincere apology from the  Cancer Center and staff concerned.  We wanted concrete evidence that the failures that occurred will not recur for other patients. 

They have done nothing about this error.  What  can I do next?