Outlook/Thunderbird is able to get the email successfully via the same server.
Below is the log from mail server using bounce program.
May 8 11:17:56 xxxx dovecot: pop3-login: Login: user=<xxxx>, method=PLAIN, rip=xxx.xxx.xxx.xxx, lip=xxx.xxx.xxx.xxx, TLS
May 8 11:17:56 xxxx dovecot...