Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Hello,
Mention how and from where was Office 2013 purchased?
Also for issues with the Microsoft Account that was used to purchase/register Office 2013, you may contact Microsoft by referring to the following link.
http://commerce.microsoft.com/help
In the help page, under Getting help click on Contact Customer Support. Select a Product, Problem type and Category. Then either click on Call Me or Start chat for more help on this issue.
Hope this information helps you. In case you need assistance with the Office applications, reply to us.
Thank you.