You've defined your incoming mail server as IMAP, but given it a server address of pop.mail.yahoo.com, and an incorrect port #.
See the following two links for possible issues getting your mail.
https://help.yahoo.com/kb/fix-pop-imap-client-sending-receiving-issues-sln3792.html
https://help.yahoo.com/kb/generate-third-party-passwords-sln15241.html
See below for IMAP and POP server settings.
How POP and IMAP differ
IMAP (Internet Message Access Protocol) is a newer protocol that allows you to remotely access and manage your email. What you do in the app affects email on the email server.
2-way sync - Emails stay on the server and are accessed remotely.
Full access - Access every email from every folder using the app.
Record of sent email - Email you send using the app is saved on the server.
Manage mailbox once - Emails deleted or moved in the app are deleted or moved on the server.
POP (Post Office Protocol) is an older protocol that copies emails from the email server to the app. Actions performed in the app don't affect email on the email server.
1-way sync - Only downloads email from the server.
Limited access - Only download emails from the Inbox.
No record of sent email - Emails sent from the app are not saved on the server.
Manage Inboxes independently - Deleting or moving email in the app isn't reflected on the server.
Keep email on server options - Different settings allow you to leave a copy of your email on the server, or delete it when it's downloaded.
Use these settings for IMAP...
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
Your login info
Email address - Your full email address ([email protected])
Password - Your account's password
Requires authentication - Yes
Source: https://help.yahoo.com/kb/SLN4075.html
Update #1:
Use these settings for POP...
POP (Post Office Protocol) is 1 way to get Yahoo Mail in a desktop or mobile app. POP downloads copies of your email, so you can move and delete them in the app without affecting the original emails.
POP settings for Yahoo Mail
Incoming Mail (POP) Server
Server - pop.mail.yahoo.com
Port - 995
Requires SSL - Yes
Outgoing Mail (SMTP) Server
Server - smtp.mail.yahoo.com
Port - 465 or 587
Requires SSL - Yes
Requires TLS - Yes (if available)
Requires authentication - Yes
Your login info
Email address - Your full email address ([email protected].)
Password - Your account's password.
Requires authentication - Yes
Source: https://help.yahoo.com/kb/pop-access-settings-instructions-yahoo-mail-sln4724.html