Hi. I've problem with ISPConfig 3.1.14p2 on Debian9: I have a multiple vhosts in apache - domain1.tld and domain2.tld, when i add a ssl certificate (not let's encrypt) to domain1.tld it's ok, it work ok. But when I later add cert for domain2.tld then domain1.tld have wrong cert - it used domain2.tld cert. Curl returns: SSL: certificate subject name (domain1.tld) does not match target host name 'domain2.tld' I've checked /etc/apache2/sites-enabled/domain1.tld.vhost nad for domain2 too - there are different cert paths, and cert files are ok - i've check it by openssl tool. Apache 2.4.25 support SNI.
Ensure that all sites use * or all sites use the IP address in ipv4 field, do not mix * and Ip on a server.