Cannot login to secondary email address on new Mac

Fastdude wrote:

Just switched to Mac Studio from old iMac. Running Ventura. I have two email addresses in Mail, both Apple addresses. One is primary for the Mac, iPhone, iPad, iCloud, iTunes, TV, etc. The other is secondary, used only for email, but for a lot of email. It also has access to iCloud, so it is synced with Mail on iPhone and iPad, where it continues to receive/send email.

This secondary address continues to work on iPhone and iPad, but, on Mac Studio, Mail keeps asking for its password. I enter it, but nothing happens. It is the correct password, because it opens iCloud in Safari on the same Mac Studio.

Suggestions?

Is it still set up in Mail>Settings>Accounts....? Verify all the information there

Add and remove email accounts on iPhone - Apple Support