Add User not showing any results

Having a weird issue with trying to add new AD users.

Currently on 2020.2.5.

I am logged into the the web console through my elevated account.  When I go in and try and add a new user I constantly get Zero results when searching AD.  Even for my very own account.  I have tried 'Domain\UserName' and 'Domain\*'

I've tried 2 separate accounts, one that is logging in via AD Group, and one that is locally added previously.  I can't add a new AD Group either.

I went and checked my LDAP settings, all are correct, and I am able to test my connect successfully.

I've even gone down the route of checking communication ports between the Application Server and the DC. 

In all the places I can think of looking, it looks fine and set correctly. 

At a loss now.