Expired activation code that isn't

I am trying to activate AVG Ultimate on another computer. I have only use 6 of the available 10 devices allocated to my subscription. I have added the user to my 'Family Sharing'. The new user has created an AVG account. I then downloaded AVG Internet Security to the new computer and when I entered my activation code a pop up says that the code has expired.

Hello Neil,

We are sorry for the inconvenience caused. We will help you to activate AVG Ultimate subscription. It isn't recommended to share account/order, personal info over this public post.

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