Cancel my Roku account as I have never used it. Effective immediately. Thank you, and you are welcome for the free money I have given you. All done now.
Other than buying the Roku itself, you haven't "given" any money to Roku. If you subscribed to something through Roku, yes they receive a portion, but you also receive the subscription, so again you haven't "given" them anything. If you are saying that something was subscribed to through Roku without your permission, then that's naturally something that should be addressed. If it wasn't subscribed through Roku, then Roku received nothing else from you.
If you've used a Roku device, you've used your Roku account. There is no cost for anything to do with a Roku account. Again, a subscription to something is not a charge for a Roku account. If someone charged you for anything to do with your Roku account, other than subscribing to something through Roku, then you paid a scammer, not Roku.
Dan Roku Stick (3600), Ultra (4640), Ultra (4670), Ultra (4800), Premiere (3920), Insignia 720p Roku TV, Sharp 4K Roku TV, Nvidia Shield, Windows 10 Pro x64 running Serviio and Plex on a wired Gigabit network.