Setting up multiple mail servers?

I have multiple websites on my cloud server each with its own child mail.domain.com

SSL is issued for each mail.domain.com mail server and DKIM is configured
Achieve 10/10 Email score with CyberPanel! - CyberPanel

It was working fine and received 10/10 but now get the following error for other pop servers (mail.domain2.com)
ERROR from Gmail: Server returned error “SSL error: Leaf certificate is self-signed”

And when trying to setup mail.domain3.com, I get the same even though SSLs are issued for all
ERROR: Unable to establish secure SSL connection to mail.domain3.com
Server returned error: “SSL error: Leaf certificate is self-signed”

I found this 6 - Self-signed SSL error on Outlook/Thunderbird - CyberPanel

And this is what is in my dovecot.conf

I notice mail.mail for the 2nd domain even though the child is mail.domain2.com

I also notice that the ending slug for domain2 and domain3 are different from domain1 and all are different from what’s in the doc

/fullcm, /privkem vs /fulm, /privem vs /m or no slug
vs
/privkey.pem and /fullchain.pem (doc)

?

I was able to get mail.domain2.com to work, edited the dovecot.conf

However I am still getting the SSL error for mail.domain3.com, I noticed there is no “cert.pem” file in etc/letsencrypt/live/mail.domain3.com whereas the other domains do