If you are unable to find the key in your email, you can retrieve it from the Microsoft store:
https://www.microsoftstore.com
Click “sign in” in the upper right, and sign in with the Microsoft Account you used to purchase the software. Then click “digital content”, and you’ll be able to see all
of your product keys.
If you have any trouble, you can contact the Microsoft Store:
https://www.microsoftstore.com/store/msusa/en_US/DisplayHelpContactUsPage/
Hope that helps!
-Dan from the Songsmith team