If you facing issue like below when checking your mail server using checktls.com, below is my temporary solution.
Login to your Cyberpanel server using ssh and run command below once each line:
postmap -F hash:/etc/postfix/vmail_ssl.map
systemctl restart dovecot
systemctl restart postfix
After apply above command, test again and you should get result like below:
Please remember this is just temporary fix, same problem will be repeated after your mail server ssl is renewed.
Sorry for my broken English.