There is your hint:
Mar 20 09:38:57 ks3100290 postfix/trivial-rewrite[18853]: warning: do not list domain too.gy in BOTH mydestination and virtual_mailbox_domains D.
There is your hint:
Mar 20 09:38:57 ks3100290 postfix/trivial-rewrite[18853]: warning: do not list domain too.gy in BOTH mydestination and virtual_mailbox_domains D.