That's odd, what is your diagnosis? Did they literally tell you your disorder is not recognized, or are you being figurative? If it's just a matter of them not knowing what schizoaffective disorder is then have your doctor change the diagnosis to bipolar disorder or schizophrenia. I find it hard to believe they would refuse to recognized a serious mental illness as a disability.

In Illinois, the state is helping with my Medicare premiums and drug copays. Lutuda now costs me like $3, it's been a godsend. I have no knowledge of Indiana's system, but the following links might offer some assistance.

I have never had a problem with a provider refusing Medicare part B reimbursement, what they typically refuse is Medicaid. Your part B benefits are not through Humana. it sounds like your problem is with your Medicare part D plan (which I assume is Humana), which is not the same as your part A or B benefits. You need to enroll in a different Medicare part D plan, there are more options then Humana. Use the Medicare plan finder (link below) to find a new part D plan.

Save on drug costs | Medicare.gov
State Pharmaceutical Assistance Programs
https://www.medicare.gov/find-a-plan...ions/home.aspx
https://www.humana.com/medicare/prod...are-drug-list/

What you need to do is print out your Medicare part D provider's formulary and take it with you on your next appointment, with the formulary your doctor will be able to swap your current medications out with tier 1 medications that your plan covers. If there is no tier 1 equivalent sometimes doctors will give out free samples indefinitely, or the pharmaceutical company will offer a patient assistance or discount program. Don't forget to consider over the counter treatment options.