Fix forwarding in sieve

data/conf/dovecot/dovecot.conf

@@ -231,4 +231,5 @@ dict {
 remote 127.0.0.1 {
   disable_plaintext_auth = no
 }
+submission_host = postfix:588
 mail_max_userip_connections = 500

data/conf/postfix/main.cf

@@ -9,7 +9,7 @@ smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated defer_una
 alias_maps = hash:/etc/aliases
 alias_database = hash:/etc/aliases
 relayhost =
-mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
+mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128 172.22.1.0/24
 mailbox_size_limit = 0
 recipient_delimiter = +
 inet_interfaces = all