Renewed site certificate displays "mail.example.com" instead of "www.example.com" on common name
I am currently on a host that provides free SSL using Let's Encrypt where the certificate is automatically renewed every three months.
After the auto-renewal I examined my cert and it displays "mail.example.com" as the common name instead of "www.example.com" (added a screenshot below). Is this normal? The reason I am asking is that my Android app can no longer communicate with my service after the renewal. Within the app it displays Unexpected end of stream on com.android.okhttp.Address error.
The renewal of the SSL is done by a module in DirectAdmin. If the certificate should display "www." Then, can I assume this is an issue with module not renewing properly? How do I communicate the issue to the host? Note that Firefox displays that the site is secure.
