Hi @Roc5,
Welcome to the Roku Community!
For more information about that channel's account authentication functionality, It's best to reach out directly to get the channel going on your Roku. They can resolve the error you are having with the channel login. Please be noted that Roku doesn't manage channel logins or authentication and many channels on Roku are developed and maintained by the channel provider themselves.
You can reach Discovery+ support here
We appreciate your patience with this matter.
Best regards,
Mary
