SSL certificate for domains associated issue!

[xtz]

Ubuntu 18.04
Webmin version |1.962|
Virtualmin version |6.14|
Hi there,
I have some issues with ssl cert.
I put screenshots to be easier to explain:

At let’s encrypt tab in front of Request certificate for Domains associated with this server it shows also subservers requesting for webmail.domain.tld also for admin.domain.tld.
If i let it like this, when i request certificate, it throw errors for dns from webmail and admin subdomains.
I combat this error by adding manual domains list underneath, by adding only domain.tld, www.domain.tld and mail.domain.tld
It will succed creating certificate, but something is wrong with certificate issuer name, look photo below:

At certificate issuer it shows: CN=R3 instead of R3 Let’s Encrypt
However, the website doesn’t show any problems if i let it like this.
If i try default domains associated for all subdomains: www, admin, webmail i get this error:

So, i don’t understand why default associated domains shows those 3 subdomains: webmail, admin and mail.
On the same server, i have multiple virtual servers set with a main domains and there things looks ok.
Look 2 prints from another virtual servers:

As you can see in the printscreens, on this server everything working nice, but the domains associated with this server shows only 2 subdomains : domain.tld and www.domain.tld by default.
And look carefully at the second foto how the issuer name is listed on this certificate!
How can i fix this?
Thanks

[calport]

Two quick comments:

1. R3 is okay. I see many of my virtual servers have this as CA too.

2. in newer versions of Virtualmin, the admin subdomain has been given more prominence and made part of the default set of domains for which certs are requested.

[xtz]

Thanks for explaining.
So, is there a way to modify that default list which include admin as subdomain? I want to delete the last 3 subdomains … admin/webmail and mail subdomains!
I am not sure what do you mean with newer version of virtualmin, because on same server with same virtualmin i have another virtual servers and all of them have default associated domains witrh same server and they don’t have admin/mail/webmail as subdomains. You can see in the last 2 images, those are from same machine.
If i use default list with admin as subdomain at request certificate, i get the error. So, what is the point of having admin and webmail as default in virtualmin if i cannot get certificate for them.