About Email setup and sending email

[a13519]

mail.err:
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Oct 8 11:13:22 usov dovecot: auth-worker: Error: mysql(localhost): Connect failed to database (zpanel_postfix): Access denied for user 'postfix'@'localhost' (using password: YES) - waiting for 125 seconds before retry
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mail.log
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Oct 9 23:24:25 usov postfix/smtp[2242]: 43021444BC: to=<a13519@icloud.com>, relay=mx1.mail.icloud.com[17.172.34.9]:25, delay=3.2, delays=0.05/0.02/1.5/1.7, dsn=2.5.0, status=sent (250 2.5.0 Ok, envelope id 0ND6003IKO4N4F60@st11p00mm-smtpin003.mac.com)
Oct 9 23:24:25 usov postfix/qmgr[1039]: 43021444BC: removed
Oct 9 23:24:33 usov postfix/smtpd[2236]: connect from unknown[125.37.155.168]
Oct 9 23:24:33 usov postfix/smtpd[2236]: NOQUEUE: reject: RCPT from unknown[125.37.155.168]: 454 4.7.1 <a13519@icloud.com>: Relay access denied; from=<a13519@3maohost.com> to=<a13519@icloud.com> proto=ESMTP helo=<[10.10.50.103]>
Oct 9 23:24:33 usov postfix/smtpd[2236]: disconnect from unknown[125.37.155.168]
Oct 9 23:27:53 usov postfix/anvil[2238]: statistics: max connection rate 1/60s for (smtp:127.0.0.1) at Oct 9 23:24:22
Oct 9 23:27:53 usov postfix/anvil[2238]: statistics: max connection count 1 for (smtp:127.0.0.1) at Oct 9 23:24:22
Oct 9 23:27:53 usov postfix/anvil[2238]: statistics: max cache size 2 at Oct 9 23:24:33
Oct 9 23:32:15 usov postfix/qmgr[1039]: 6048644467: from=<root@usov.3maohost.com>, size=703, nrcpt=1 (queue active)
Oct 9 23:32:51 usov postfix/smtp[2327]: 6048644467: to=<root@usov.3maohost.com>, orig_to=<root>, relay=none, delay=60577, delays=60540/0.03/37/0, dsn=4.4.6, status=SOFTBOUNCE (mail for usov.3maohost.com loops back to myself)
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