Identify the system account relationship
Apple TV can hold a TV-provider relationship separately from an application’s ordinary profile. Check which provider is configured and whether Adult Swim has permission to use it. This can explain why the app appears to remember a provider you did not just type.
Do not confuse the Apple ID used for the app store with the television package used to unlock a broadcaster. They perform different roles, even on the same device.
Follow the published route for that permission state
Adult Swim’s official help describes Provider Login with a provider selection where system access has been permitted. Without that permission, it describes using the URL shown on screen, selecting the device and entering the displayed code before provider sign-in.
Use the current screen’s code rather than an old photograph or a code from another television. Complete the process yourself on a trusted phone or computer. Temporary codes are not credentials for a separate IPTV player.
Verify the package before treating authentication as broken
A recognised provider login still needs the actual television package to include Adult Swim. If the provider rejects the channel entitlement, changing the Apple TV permission cannot be promised to add the missing package. Check the provider’s account details.
Try a free marathon separately if you need a basic video comparison. Free playback can work without proving that the provider-required content is authorised.
Record the point where the flow changes
For support, say whether Adult Swim had system-provider permission, which route you followed, whether provider sign-in succeeded and the exact final message. Include the Apple TV model and tvOS version. These observations help locate the issue without exposing account secrets.
After changing permissions, confirm which provider the app now shows before making more changes. Repeatedly clearing every device account at once makes it difficult to tell whether the original problem was an outdated provider selection, failed device linking or a genuine channel-package restriction.
Questions about this guide
Can the system TV Provider permission change the login route?
Yes. Adult Swim’s official Apple TV help separates the two cases.
Can changing that permission add a missing TV channel package?
No. The provider’s actual subscription entitlement remains a separate requirement.