I get this error even after clicking provision in the lets encrypt tls admin interface.
I did also rerun the setup.
The TLS (SSL) certificate for this domain is currently self-signed. You will get a security warning when you check or send email and when visiting this domain in a web browser (for webmail or static site hosting).
It only shows up for the subdomain (i.e the actual hostname of the box).
How do I get a lets encrypt cert installed for the subdomain?