My Cox Email has been migrated to Yahoo. I have configured the Network Configuration in PMail for Yahoo. I am using POP. I can retrieve/delete my email for my Cox Account on Yahoo.

I've generated an APP password for PMail.

I'm unable to Send (SMTP) from PMAIL to Yahoo. This is the Trace showing end of transaction. I've masked the sending and recipient email address in the trace.

Can someone tell me what I'm doing wrong in my configuration?

19:18:15.371: >> 220 smtp.mail.yahoo.com ESMTP ready
19:18:15.371: << EHLO [192.168.168.11]
19:18:15.402: >> 250-hermes--production-ne1-79ddd986d8-qbr42 Hello [192.168.168.11] [72.209.145.48])
19:18:15.402: >> 250-PIPELINING
19:18:15.402: >> 250-ENHANCEDSTATUSCODES
19:18:15.402: >> 250-8BITMIME
19:18:15.402: >> 250-SIZE 41697280
19:18:15.402: >> 250 AUTH PLAIN LOGIN XOAUTH2 OAUTHBEARER
19:18:15.402: << AUTH LOGIN
19:18:15.449: >> 334 VXNlcm5hbWU6
19:18:15.449: << amN1cnRpczEzQGNveC5uZXQ=
19:18:15.480: >> 334 UGFzc3dvcmQ6
19:18:15.480: << eWFwYWtreWRqY2VlemdxeA==
19:18:16.105: >> 235 2.7.0 Authentication successful
19:18:16.105: << MAIL FROM: SIZE=436
19:18:16.293: >> 250 2.1.0 Sender xxxxxxx13@cox.net OK
19:18:16.293: << RCPT TO:yyyyyyy@gmail.com
19:18:16.324: >> 250 2.1.5 Recipient yyyyyyy@gmail.com OK
19:18:16.324: << DATA
19:18:16.355: >> 354 Ok Send data ending with <CRLF>.<CRLF>
19:18:16.480: >> 550 Request failed; Mailbox unavailable

Really appreciate any help that I can get.

Thank in advance!