我收到错误，例如
Feb 11 05:45:07 htz postfix/sendmail[6465]: fatal: User web6(5006) is not allowed to submit mail
Feb 11 05:45:56 htz postfix/sendmail[6466]: fatal: User web21(5012) is not allowed to submit mail
Feb 11 05:54:24 htz postfix/sendmail[6605]: fatal: User web21(5012) is not allowed to submit mail
Feb 11 05:54:39 htz postfix/sendmail[6607]: fatal: User web21(5012) is not allowed to submit mail
Feb 11 05:54:54 htz postfix/sendmail[6608]: fatal: User web21(5012) is not allowed to submit mail
Feb 11 05:55:09 htz postfix/sendmail[6666]: fatal: User web21(5012) is …postfix ×1