Help & troubleshooting for channels on your Roku device, including adding/removing channels, logging in to, authenticating, or activating a channel, channel-specific playback issues, assistance contacting channel publishers to report issues, and adjusting channel-specific settings.
Doubtful. Roku has a "all subscriptions are prepaid and nonrefundable" policy, but you can try going through that support link. It's not generally easy to subscribe to something without knowing it, but you may want to set up a PIN so that no purchases can be made without entering the PIN: https://my.roku.com/account/pin
Do you have more than one Roku linked to your account? You can see all your linked devices at https://my.roku.com