Looks like you're using a mobile phone to change your channel art. To update your banner, you'll need to be on a computer. Check out this article for instructions: https://yt.be/help/sg6D . Let us know if this helps!
-
-
Thanks. Twitter will use this to make your timeline better. UndoUndo
-
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.