Hide My Email of Macbook Pro Mail app doesn't generate an email address

See the article Use Hide My Email in Mail on Mac - Apple Support

• View and update your Hide My Email settings: Click Settings in the banner shown across the top of the message, or Control-click Hide My Email in the To field, then choose Go to Hide My Email Settings.

Read Create and edit Hide My Email addresses on iCloud.com - Apple Support

See the section - Change the forwarding address .

Reply to or forward emails in Mail on Mac - Apple Support

Hey there ChrisF205,

Thanks for reaching out to Apple Support Communities. We're happy to provide some assistance.

You can change the "Forward To" email address by following the actions under the "Change the forwarding address" section here:

Create and edit Hide My Email addresses on iCloud.com - Apple Support

Every unique, random address you create with Hide My Email is forwarded to the same email address. You can change the forwarding address at any time.

1. On iCloud.com, go to Account Settings, then click Manage in the Hide My Email section.

2. Scroll to the “Forward to” section, then choose a different address.

3. The “Forward to” section is below your list of active addresses and above your inactive addresses.

Note: You can forward your unique, random addresses to an email address associated with your Apple ID. To add or remove an address, go to the Apple ID account website.

We hope this helps.

Have a great day!

ChrisF205,

Thanks for the reply. We'd like to double-check one point to see if we can narrow this down. Your earlier screenshot mentions making sure your account is set up in the Mail app. Try clicking Apple menu () > System Preferences > Internet Accounts, and then click your account in the left-hand column. Is Mail toggled on there? We want to make sure it's configured there before proceeding.

Take care.