hi as per mail log, mailserver is sending email to itself and getting failed and doing it continuously.
My port 25 is working fine and sending and receiving email manually is working fine.

Here is log of same

2025-01-03T18:16:45.272227+05:30 mail postfix/pickup[526196]: 4262140D94: uid=0 from=root@mail.hostname.com
2025-01-03T18:16:45.278576+05:30 mail postfix/cleanup[527092]: 4262140D94: message-id=20250103124645.4262140D94@mail.hostname.com
2025-01-03T18:16:46.472048+05:30 mail postfix/qmgr[1833]: 4262140D94: from=root@mail.hostname.com, size=2660, nrcpt=1 (queue active)
2025-01-03T18:16:50.613311+05:30 mail postfix/smtp[527094]: 4262140D94: to=<root@localhost>, relay=none, delay=5.3, delays=1.2/0.01/4.1/0, dsn=5.4.6, status=bounced (mail for localhost loops back to myself)
2025-01-03T18:16:50.614462+05:30 mail postfix/cleanup[527092]: 95B8F40D95: message-id=20250103124650.95B8F40D95@mail.hostname.com
2025-01-03T18:16:50.617125+05:30 mail postfix/bounce[527096]: 4262140D94: sender non-delivery notification: 95B8F40D95
2025-01-03T18:16:50.617316+05:30 mail postfix/qmgr[1833]: 95B8F40D95: from=<>, size=4981, nrcpt=1 (queue active)
2025-01-03T18:16:50.617388+05:30 mail postfix/qmgr[1833]: 4262140D94: removed
2025-01-03T18:16:50.780641+05:30 mail postfix/smtpd[527011]: connect from unknown[xxx.xx.xxx.xx]
2025-01-03T18:16:50.781774+05:30 mail postfix/smtp[527094]: warning: host mail.hostname.com[xxx.xx.xxx.xx]:25 greeted me with my own hostname mail.hostname.com
2025-01-03T18:16:50.783422+05:30 mail postfix/smtp[527094]: warning: host mail.hostname.com[xxx.xx.xxx.xx]:25 replied to HELO/EHLO with my own hostname mail.hostname.com
2025-01-03T18:16:50.791862+05:30 mail postfix/smtp[527094]: 95B8F40D95: to=root@mail.hostname.com, relay=mail.hostname.com[xxx.xx.xxx.xx]:25, delay=0.17, delays=0/0/0.17/0, dsn=5.4.6, status=bounced (mail for mail.hostname.com loops back to myself)
2025-01-03T18:16:50.792211+05:30 mail postfix/qmgr[1833]: 95B8F40D95: removed
2025-01-03T18:16:50.792887+05:30 mail postfix/smtpd[527011]: disconnect from unknown[xxx.xx.xxx.xx] ehlo=1 quit=1 commands=2
2025-01-03T18:17:15.612315+05:30 mail postfix/pickup[526196]: 9561C40D94: uid=0 from=root@mail.hostname.com
2025-01-03T18:17:15.613787+05:30 mail postfix/cleanup[527092]: 9561C40D94: message-id=20250103124715.9561C40D94@mail.hostname.com
2025-01-03T18:17:15.985097+05:30 mail postfix/qmgr[1833]: 9561C40D94: from=root@mail.hostname.com, size=7806, nrcpt=1 (queue active)
2025-01-03T18:17:22.166591+05:30 mail postfix/smtp[527094]: 9561C40D94: to=<root@localhost>, relay=none, delay=6.6, delays=0.38/0/6.2/0, dsn=5.4.4, status=bounced (Host or domain name not found. Name service error for name=localhost type=AAAA: Host not found)
2025-01-03T18:17:22.168231+05:30 mail postfix/cleanup[527092]: 28AFD40D95: message-id=20250103124722.28AFD40D95@mail.hostname.com
2025-01-03T18:17:22.170610+05:30 mail postfix/bounce[527096]: 9561C40D94: sender non-delivery notification: 28AFD40D95
2025-01-03T18:17:22.170902+05:30 mail postfix/qmgr[1833]: 28AFD40D95: from=<>, size=10247, nrcpt=1 (queue active)
2025-01-03T18:17:22.170978+05:30 mail postfix/qmgr[1833]: 9561C40D94: removed
2025-01-03T18:17:24.338392+05:30 mail postfix/smtpd[527011]: connect from unknown[xxx.xx.xxx.xx]
2025-01-03T18:17:24.339507+05:30 mail postfix/smtp[527094]: warning: host mail.hostname.com[xxx.xx.xxx.xx]:25 greeted me with my own hostname mail.hostname.com
2025-01-03T18:17:24.340712+05:30 mail postfix/smtp[527094]: warning: host mail.hostname.com[xxx.xx.xxx.xx]:25 replied to HELO/EHLO with my own hostname mail.hostname.com
2025-01-03T18:17:24.347973+05:30 mail postfix/smtp[527094]: 28AFD40D95: to=root@mail.hostname.com, relay=mail.hostname.com[xxx.xx.xxx.xx]:25, delay=2.2, delays=0/0/2.2/0, dsn=5.4.6, status=bounced (mail for mail.hostname.com loops back to myself)
2025-01-03T18:17:24.348545+05:30 mail postfix/qmgr[1833]: 28AFD40D95: removed
2025-01-03T18:17:24.348956+05:30 mail postfix/smtpd[527011]: disconnect from unknown[xxx.xx.xxx.xx] ehlo=1 quit=1 commands=2
2025-01-03T18:17:51.862650+05:30 mail postfix/pickup[526196]: D272840D94: uid=0 from=root@mail.hostname.com
2025-01-03T18:17:51.863441+05:30 mail postfix/cleanup[527092]: D272840D94: message-id=20250103124751.D272840D94@mail.hostname.com
2025-01-03T18:17:52.317257+05:30 mail postfix/qmgr[1833]: D272840D94: from=root@mail.hostname.com, size=2702, nrcpt=1 (queue active)
2025-01-03T18:17:56.440472+05:30 mail postfix/smtp[527094]: D272840D94: to=<root@localhost>, relay=none, delay=4.6, delays=0.46/0/4.1/0, dsn=5.4.6, status=bounced (mail for localhost loops back to myself)
2025-01-03T18:17:56.441657+05:30 mail postfix/cleanup[527092]: 6B8E340D95: message-id=20250103124756.6B8E340D95@mail.hostname.com
2025-01-03T18:17:56.444461+05:30 mail postfix/bounce[527096]: D272840D94: sender non-delivery notification: 6B8E340D95
2025-01-03T18:17:56.444701+05:30 mail postfix/qmgr[1833]: 6B8E340D95: from=<>, size=5023, nrcpt=1 (queue active)
2025-01-03T18:17:56.444766+05:30 mail postfix/qmgr[1833]: D272840D94: removed
2025-01-03T18:17:58.678467+05:30 mail postfix/smtpd[527011]: connect from unknown[xxx.xx.xxx.xx]
2025-01-03T18:17:58.679673+05:30 mail postfix/smtp[527094]: warning: host mail.hostname.com[xxx.xx.xxx.xx]:25 greeted me with my own hostname mail.hostname.com
2025-01-03T18:17:58.680871+05:30 mail postfix/smtp[527094]: warning: host mail.hostname.com[xxx.xx.xxx.xx]:25 replied to HELO/EHLO with my own hostname mail.hostname.com
2025-01-03T18:17:58.689190+05:30 mail postfix/smtp[527094]: 6B8E340D95: to=root@mail.hostname.com, relay=mail.hostname.com[xxx.xx.xxx.xx]:25, delay=2.2, delays=0/0/2.2/0, dsn=5.4.6, status=bounced (mail for mail.hostname.com loops back to myself)
2025-01-03T18:17:58.689771+05:30 mail postfix/qmgr[1833]: 6B8E340D95: removed
2025-01-03T18:17:58.690150+05:30 mail postfix/smtpd[527011]: disconnect from unknown[xxx.xx.xxx.xx] ehlo=1 quit=1 commands=2

Anyone please help me to understand how this is happening.