If there is a subscription, and you don't want it, cancel it, then submit a Billing Inquiry. Then reach out to @Hector-Roku or one of the billing reps (he's tagged, so he'll be along).
If there is no subscription listed, then Roku didn't charge you. That indicates your payment card information was compromised and the thieves submitted a payment request and gave a false name (Roku). They can do that, by the way. If this is the case, contact your bank and submit a fraud claim.
DBDukes Roku Community Streaming Expert Note: I am not a Roku employee.
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