You should be able to submit a billing issue on the Contact page.
Also, if you go to the Subscriptions page for your account, if you don't see any subscriptions, then Roku didn't bill you, but rather a scammer obtained your payment card information and submitted charges, including false descriptions. This is more common than you may realize.
If this is the case, also contact your bank and submit a fraud claim, using the printout of the emtpy subscriptions page as proof.
Roku Community Streaming Expert
Note: I am not a Roku employee.
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