Trying to cancel a premium theme

I have no idea what you mean by ‘trying to cancel a premium theme’ and you have not asked a question.

Could this a premium theme on a wordpress.com site?

Yes it is the Duet theme. Here is the link that won’t work when I try to cancel the theme. https://brigittecallieu.wordpress.com/wp-admin/paid-upgrades.php?action=canceltheme&id=28459-2726221&_wpnonce=59989af6d0

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