Serial Number and Authorization code

I have been using the 30 day trial of Sketch book pro 2018 downloaded on my macbook pro. I just bought a year paid subscription. The email confirmation does not include a serial number or authorization code. I’ve looked in the support questions and nothing I have tried has worked. How do I find or get my serial number and authorization code for my new paid account to use on a 2018 desktop version.

Version 2018 is not Subscription-compatible.
Use 2019 or 2020, instead.
There, you can sign in with the email address which bought the subscription.

Thanks for the reply. However my son’s operating system only supports 2018 and not newer. Any other ideas?

Normally you can only buy a license for the current version of SketchUp. You would need to contact their customer support to see if they would convert the license to a 2018 license. Since there is no Subscription license for 2018, they would likely expect you to buy a Classic license so you’d have to pay the difference.

Thanks for the info. I will write them again.