How to offer a single license for free without sending the manifest?

New Contributor
Hi everyone,

my Excel app is available on Microsoft AppSource and it has 14 day trial period.

A customer tested my app and gave me some very valuable feedback during his trial period.
Now, I want to give him in return one free license for his valuable feedback.
On my server I made sure he is recognized as a licensee.

My customer gets the below "Add-in Information" window saying:
"It looks like you're trying out this addin. If you bought the full-feature version of it, select Refresh. If you are signed in with your organizational account, learn how to access this add-in."

Of course, clicking on the "Buy"- or "Refresh"-button doesn't change anything.
So, can I send him e.g. a (license-)file so that he no longer gets the information window?

I appreciate any help