Hi, I have a similar problem. But, I could solve it by my self. I'm using a DS 389 directory server with SSL enabled. I could setup everything using TLS 1.2 on the ldaps port 636. Only for the authentication on directory server (which is configured correctly), the authentication did not work. I have seen message in LDAP log like this:
[04/Dec/2019:07:32:08.887004358 +0000] conn=120 op=-1 fd=65 closed - SSL peer had some unspecified issue with the certificate it received.
[04/Dec/2019:07:32:08.896911103 +0000] conn=121 fd=65 slot=65 SSL connection from x.x.x.83 to x.x.x.84
[04/Dec/2019:07:32:08.897859410 +0000] conn=121 op=-1 fd=65 closed - Peer using unsupported version of security protocol.
[04/Dec/2019:07:32:08.899690296 +0000] conn=122 fd=65 slot=65 SSL connection from x.x.x.83 to x.x.x.84
To solve this problem, I configured the LDAP server using no SSL on port 389. This works fine. But, I think, the problem should be solved by Gluu team.
Hope, this helps you ....