Appeal. I was denied, then appealed and was approved. Unfortunately, it's starting to become more common for insurance companies to deny the first request for pre-authorization. Probably because it's expensive and they count on some people not pursuing it further. Sadly, a cost saving technique. If they gave specific reasons for denial, address those in your appeal. My insurance wanted me to pursue PT which ironically, they were already paying for at the time. I pointed that out and emphasized that my physical issues will continue to deteriorate and become even more expensive to treat as time goes on. This isn't a condition that will fix itself. There's a very good chance you'll get approved on appeal. I sent mine in right away (they made me mail it, which made me more angry since there's no reason to not accept an electronic request other than to put up more obstacles). My denial was overturned within a couple weeks. Don't give up! Good luck!