Unable to run certbot command to get the ssl configs

certbot certonly --webroot --webroot-path /opt/postal/app/public --domains mail.yourdomain.com

when ever i run this command to setup ssl for postal smtp it gives error every time saying file or directory doesn’t exist

root@mail:~# certbot certonly --webroot --webroot-path /opt/postal/app/public --domains mail.headerc4dsuprt.monster
/opt/postal/app/public does not exist or is not a directory

This has been discussed previously as well. Use docker to install postal and caddy to get SSL.
Thanks