AETNA / Medicare review: Prescriptions

I bought the Aetna Medicare supplement for prescriptions for the first time turning 65. The salesperson that sold it to me had me list all my medications and the amounts I took per day. I was told that they were all covered. Now as of 5-6-2023. It’s the 3rd time I go to the required pharmacy to be told Aetna will not pay without a prior authorization so I have to go days without my medication. One medication I take 6 a day and was told they would only cover one a day. And it’s less than $50 a month. Are all the insurance companies this crappy? I never had this problem before Medicare