Thanks for letting us know about the issue that you are experiencing.
I would like to look further into this issue for you. Please send me a PM with your Roku account email address, and include the serial number of the Roku device from Settings>System>About. I'll be able to assist you further from there.
Did you get this resolved? I'm in the same boat, and customer support was no help at all. They just told me to create a new account. My concern is the saved payment information, that someone else now has access to.
Can you please clarify the issue you are experiencing?
If you need assistance with account related issues, please reach out to our support team directly here for your 'Account or billing' issue, here: https://support.roku.com/contactus. They will be able further assist you.