Hi Alexa3251,
Thanks for using Apple Support Communities! I see you have a question about your Apple TV, and I'd like to do what I can to help.
Is your Apple TV a 4th or 5th generation? If so, you'll need to download the Disney+ app to your Apple TV, as that TV show is only available though that app. Redownload apps, music, movies, TV shows, and books
For additional assistance, contact the app developer. How to contact an app developer
If you have an earlier Apple TV, 2nd or 3rd generation, you can use AirPlay to mirror your iPhone on your Apple TV to watch that show: How to AirPlay video and mirror your device's screen and AirPlay system requirements
Take care!