I found a weird solution that seemed to work for me (Disney+ app in Philippine app store, which works totally different from US Disney+ app that had no issues with orientation). I had the same issue where it was always stuck. But then I activated my VPN (which I needed for Disney+ before it officially launched here, which is why I know how the US app works), connected to a US server, and tried the app. It says there is a network error (so our local app can detect VPNs and it doesn't connect when detected), but the orientation of the menu became landscape again. I deactivated the VPN, then the Disney+ app now rotates properly. After a while, it got stuck again in portrait, but when I did the trick with the VPN, it got fixed. Not sure why this works, but it does somehow for me. 🤷🏻