How do I select which device I want to be my primary device?
MacBook Pro 15″, macOS 10.15
What fixed it for me... from the iphone go to my Settings>Messages>Send & Recieve once in make sure you apple ID email address is checked. That did it!
If Apple ID is created from Mac , and signed in system preferences , it will be a primary device , in which trusted devices are verified .
You can select the primary device from Mac system preferences > click on Apple ID , under iCloud you can see Mac book click over it , the other device list will be under it , click on view on web and sign in with account credentials , from there also other device details can be viewed Check your Apple ID device list to find where you've signed in - Apple Support
Change Devices settings for your Apple ID on Mac - Apple Support
Changing Primary Device
