i would like to cancel a subscription but my setttings is not allowing me and showing error

No, this is a user-to-user forum, we don’t even know who you are. You can contact Apple Support using the Contact Support link at the top of this page.

This Apple support link may help you resolve the problem—>See or cancel your subscriptions - Apple Support

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https://twitter.com/AppleSupport.          People have posted it may take an hour or more to get a response.