Re: serial number is already in use

It's a moot point since old Acrobat versions are unsupported & End of Life. 

Even if you had remaining activations left, dead product versions can't be activated. 

For security & compatibility reasons, use the latest Acrobat. 

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FREE Acrobat Reader -- view, comment, print & sign PDF.
https://www.adobe.com/acrobat/pdf-reader.html

Paid Acrobat Pro -- the complete solution for creating and saving PDF.
https://www.adobe.com/acrobat/acrobat-pro.html

in the future, to find the best place to post your message, use the list here, https://community.adobe.com/

p.s. i don't think the adobe website, and forums in particular, are easy to navigate, so don't spend a lot of time searching that forum list. do your best and we'll move the post (like this one has already been moved) if it helps you get responses.

<"moved from account, payment and plan">

No... if you have used up both of your allowed activations you may do nothing