First time installing community gitlap with ldap not working

Exception: SSL_connect returned=1 errno=0 peeraddr= state=error: certificate verify failed (unable to get local issuer certificate)

external_url ‘

gitlab_rails[‘ldap_enabled’] = true
gitlab_rails[‘ldap_servers’] = {
‘main’ => {
‘label’ => ‘LDAP’,
‘host’ => ‘ldaps://’,
‘port’ => 636,
‘uid’ => ‘sAMAccountName’,
‘encryption’ => ‘simple_tls’,
‘base’ => ‘dc=mte, dc=com’

gitlab-rake gitlab:check

LDAP: … Server: ldapmain
Exception: getaddrinfo: Name or service not known

Checking LDAP … Finished

May I know how to overcome this issue. Any help appreciated.

Ubuntu : 20.04

We got help from LDAP Team to resolve the LDAP with SSL issue.