Hello and welcome to justanswer, My name is ***** ***** i will be assisting you today,
I'm sorry about the issue, to cancel your avast account and disable the Automatic Renewal service, please follow the step by step instructions in the link below :
https://www.avast.com/faq.php?article=AVKB126 (please scroll down to Detailed Steps)
You can also delete your avast account by clicking on this link : https://my.avast.com/profile#deleteAccount once you login to your account using your email/username and password, click on the "Delete Account" link at the bottom of the page.
To contact avast : https://www.avast.com/contacts or https://www.avast.com/total-support
Phone number : +1-***-***-****
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