Debian 10升级至11后Postfix无法发送邮件，报错554 5.7.1 Relay access denied求助

我尝试把Debian从10版本升级到11，结果整个系统都乱套了，现在正忙着修复Postfix。目前我能正常收到邮件，但就是发不出去，每次尝试发送都会收到报错：554 5.7.1 Relay access denied

我的Postfix配置内容：

# 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 (Debian/GNU)
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

# TLS parameters
smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
smtpd_use_tls=yes
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtp_tls_session_cache_database = b...

备注：内容来源于stack exchange，提问作者Anarkie