Revoke automatically executed extension

Unfortunately, it is impossible to exercise my right to cancel the automatic renewal online. When I try to contact customer support via chat, the AI fails and I can’t get a human supporter into the chat.
What do I have to do to cancel the renewal and receive a credit note?

Norton Cancellation and Refund Policy [here]
How to request a refund for an annual renewal fee [here]
Norton annual and monthly subscription refunds [here]

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