Hello SJB2073,
Thanks for reaching out in Apple Support Communities. To get a better understanding of the issue, we'll need to ask you a few questions:
• Did you have to download the Apple TV App or was it already installed?
• Are you completing the following steps:
1. Open the Apple TV app
on your smart TV or streaming device.
2. Navigate to Settings.
3. Select Accounts, then select Sign In.
4. Follow the onscreen instructions to do either of the following:
• Sign in using an iPhone, iPad, or iPod touch (iOS 11 or later), or an Android device that supports QR scanning: Use your camera to scan the QR code that appears onscreen, then follow the instructions on your device to sign in.
• Sign in manually: Select “Sign in manually,” then follow the onscreen instructions to enter your Apple ID.
More details found here: Apple TV App User Guide - Get Started
If so, we'd like to provide you with some steps that may help resolve the loop that keeps occurring:
• Restart your devices
• Uninstall the Apple TV app and download it again. These steps may be found in your user manual or you can click here and select the model that you have:
Hisense - Support
Let us know if this helps.
Take care!