I had an issue with logging into the AppleTV channel on all of my Rokus after changing my password. I tried every suggestion I could find other than doing a Factory Reset on my Roku. For example, I confirmed my Roku was up-to-date, I removed my SD Card, I removed the AppleTV Channel, I reset my Roku, I unplugged my Roku, I turned off my TV and restarted everything. I then added the AppleTV channel, and selected the Channel and tried to log in with [Sign In or Start Free Trial]. Failure again and again whether or used the QRC Code, log in via Remote or Activate url provided!
The only thing that worked for me was the following: After removing and re-adding the Apple-Channel, when you open the Apple Channel you will be asked to select [Sign In or Start Free Trial] or [Sign in Later]. Finally (after several failed attempts trying to Sign In) I picked [Sign in Later] and then used the menu item within the AppleTV App to Sign In via the Apple Account Settings.
Once I clicked on Sign In and confirmed (or re-entered) my Apple ID, I used the camera on my Apple Phone and the QRC Code to log in. I finally had Success!
Once I learned to use Sign in Later - I went to my Roku Stick, I did remove the Channel, reset my Roku, re-added the Apple channel and then picked [Sign in Later], used the QRC code and it worked the first time. I hope this helps!
