Just click on this link: https://my.roku.com/account/close
that will open your roku account page from your computer,
sign in to your account when prompted,
then click on the link once more if necessary, and it will take you to the account deactivation page.
click on Continue, and it will ask for a confirmation that you really want to close your account, and then the process is complete.
Your account is deleted, all payment info cleared, etc. You wouldn't get any further roku charges at that point.
Note that if you signed up for any paid streaming services though, like netflix or hulu for example, those are handled through those sites individually, cancelling roku will not stop charges to specific apps.
If you have any other questions, just let me know. Otherwise, please take a moment to rate my service using the stars at the top of the page; hopefully I have earned 5 Stars. I also invite you to contact me directly with any future support needs at http://bit.ly/1QwLxGh and ask for Nathan.
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