Within that info, the *button Remove Channel option is not available if your subscription to Fubo is billed by Roku.
I would assume you have to go your Account Dashboard and Manage Subscriptions from there before being able to remove channel.
Since these channels are mostly developed and managed by others, a good resource for this info is to go directly to the channel's help/support page for more info.
1-844-551-1005 is Fubo's support. https://support.fubo.tv/hc/en-us main help page
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
Insignia RokuTV, Ultra 4660x, Premiere+ 3921, Express 4k+ 3941