Thanks for the information.
You most likely signed up for a subscription through Roku as well as with the channel provider directly.
To manage your subscriptions on your Roku account, sign into your Roku account on my.roku.com. Once logged in, click Manage my subscriptions.
For more information, visit our Support page here: How do I manage or cancel a Roku-billed subscription?
To manage your subscription with Starz directly, you will need to contact Starz support. You can reach them here: https://www.starz.com/us/en/faq
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