iTunes 12.9.5.5 movie rental not available on apple-tv

Not sure why you would rent from iTunes if you intend to watch on Apple TV. Seems like unnecessary extra steps.

Rent movies from the Apple TV app - Apple Support

- As soon as you press play, you have 48 hours to finish watching your rental. After that time, the listing will be gone.

Check if the rental was processed completely. See your purchase history for the App Store or iTunes Store - Apple Support

Hello,

iTunes Store rentals are not shareable between devices. You would have needed to rent this movie directly from your Apple TV.

As far as I know, that is still possible. Remember to choose ‘Watch later’ at the end of the renting process, to delay the start moment for the 48 hour renting period.