Postfix重启及表单邮件脚本服务器端失效问题排查求助

各位好，我碰到一个搞不定的问题：我写了个提交表单数据到邮箱的脚本，在本地主机测试的时候完全正常，可是部署到服务器上就彻底不管用了。

我把Postfix的main.cf配置内容贴在下面，麻烦大家帮我排查下可能的问题点：

# See /usr/share/postfix/main.cf.dist for a commented, more complete version

# Debian specific:  Specifying a file name will cause the first
# line of that file to be used as the name.  The Debian default
# is /etc/mailname.
#myorigin = /etc/mailname

smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu)
biff = no

# appending .domain is the MUA's job.
append_dot_mydomain = no

# Uncomment the next line to generate "delayed mail" warnings
#delay_warning_time = 4h

readme_directory = no

# See http://www.postfix.org/COMPATIBILITY_README.html -- default to 3.6 on
# fresh installs.
compatibility_level = 3.6

# TLS parameters
smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key

smtp_tls_CApath=/etc/ssl/certs
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache

smtpd_relay_restrictions = permit_my...

目前我已经确认脚本逻辑在本地是没问题的，服务器上也给脚本设置了相应权限，Postfix服务也重启过好几次，但邮件就是发不出去。有没有大佬能帮忙分析下哪里可能出问题了？

备注：内容来源于stack exchange，提问作者Adi Mehmedičević