There is no fee to use Roku. There are subscriptions that you can pay for through Roku -- Netflix, etc -- but if you aren't subscribing to a service, then there is no fee.
I suspect you're saying that an item has appeared on your payment card statement that purports to be from Roku. Go to your Roku Subscriptions page and see what shows there. If there's nothing, then it's not Roku, but rather you have a compromised payment card that some scammer/thief submitted with "Roku" in the description. If that's the case, contact your financial institution and issue a fraud claim. And reach out to @Jeremiah-Roku as he's a primary contact for things like this.
And if you do have a compromised payment card, you'll want to take action sooner rather than later, if your payment card information is floating around the dark Web.
DBDukes Roku Community Streaming Expert Note: I am not a Roku employee.
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