Integrating CA into LDAP


I’m using the nextcloud:apache-stable image in a docker container and I want to add a LDAP Server to the configuration. So far I could do this in the Admin Setting and a view things in the database. The problem is that the LDAP Server uses a Certificated authorized by a custom CA.
I added the CA.pem and added it via update-ca-certificates.
But LDAP doesn’t seem to recognize it. At least everything works fine if the “Turn off SSL certificate validation”-value is true but if it is false the Error massage is “Connection lost”.
Does someone know how to integrate the CA into LDAP?

Thanks in advance!