I just activated Cam+ licenses and encountered these same issues. Here’s what works. Clicking those Redeem buttons in the redeem email isn’t enough.
Clicking the “Redeem” button opens a browser tab. You have to select the “Redeem” tab at the top of the browser page.
Then paste the redemption codes from the email in the box, and press “Apply”.
Typical Wyze. They could have automated these steps with the “Redeem” button.