I would like to point out that I am an elderly person and I am using my account via the Outlook application now. The matter concerns my account.
For about three or four weeks, the Outlook application has stopped downloading emails from your servers, or most likely the other way around, your servers have stopped cooperating with the Outlook application. After many checks of the server configuration settings, both smpp and imap, it turns out that the problem is on your side. This problem also concerns the email boxes of my mother and my wife.
My settings:
Incoming Mail (IMAP) Server
• Server - imap.mail.yahoo.com
• Port - 993
• Requires SSL - Yes
Outgoing Mail (SMTP) Server
• Server - smtp.mail.yahoo.com
• Port - 465 or 587
• Requires SSL - Yes
• Requires authentication - Yes
New app password generate - done.

Firewall and antivirus are disabled! My settings are correct. It seems something has changed on the Yahoo portal (about 3 weeks ago)- in your case: a change to "the latest security protocols" required by Yahoo Mail??

I urgently need your help to fix this serious problem. Please send me feedback on my email address.