If mails are not receiving on one of the plesk email ID ,follow the below steps.
IT happen because of missing information about that email id in plesk Database
1.Take ssh of plesk server with root.
2.Type below command to check if there information about that mail id in plesk database
# postmap -s /var/spool/postfix/plesk/
virtual | grep "[email protected]"
Kindly remove quotes before executing command if got nothing after executing this command it means that email id's information missing from database.
2.Type below command to reconfigured the configuration of that mail id
# plesk repair mail "example.com" -y
Kindly remove quotes before executing command and use your email id domain which have issue instead of example.com
Now you can able to receive mail.