Not able to login to GitLab using AD account after LDAP URL change

Not able to login to Gitlab using existing AD account after LDAP URL change, same is working for Jenkins, Portainer etc…

Upgraded GitLab to latest version and tried, still same issue. Getting below error
Could not authenticate you from Ldapmain because "Connection reset by peer @ io fillbuf - fd:53 ".

please advise
Thanks in advance