Denied for a medication Ive been on for 3 years because they changed the formulary

Been taking the same medication for 3 years with no issues. Went to refill it last week and got denied. Turns out my insurance changed their formulary at renewal and my medication is no longer covered.

No warning. No transition period. No letter. Just showed up at the pharmacy and got told itll be $600 out of pocket for something I NEED and have been taking without issues.

Now I have to go back to my doctor, try two "preferred alternatives" that didnt work for me before (thats why my doctor originally prescribed this one), and then MAYBE get an exception approved.

Who decided this? Some executive at the insurance company overriding my doctor? This is healthcare decisions being made by accountants.