AS @renojim indicated, many scammers will submit charges against compromised payment cards and put false information regarding the details of the charge. They'll put Roku, Hulu, Disney, Warner, HBO, and other entities that did not make the charge. They do this to throw the cardholder off.
Since you didn't have a Roku account, it's obviously fraud. The main concern should probably be that your card is compromised.
Contact your bank and issue a fraud claim.
DBDukes Roku Community Streaming Expert Note: I am not a Roku employee.
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