As per the description above, you want to cancel the current Adobe PDF Pack subscription, Is that correct?
Please refer to the following KB doc for the cancellation Learn about cancelling your Adobe Creative Cloud plan subscription Link: https://helpx.adobe.com/manage-account/using/cancel-creative-cloud-subscription.html
You may also contact the Adobe support team for more assistance through https://helpx.adobe.com/in/contact.html
I have also sent you the direct contact number for Adobe support via private message, please check your email inbox.
Hope this helps and let us know how it goes.