I upgraded SharePoint 2010 to 2013 to 2016. I'm unable to successfully sync AD with SharePoint 2016 User Profile Service. I followed instructions here https://docs.microsoft.com/en-us/sharepoint/administration/configure-profile-synchronization-by-using-sharepoint-active-directory-import. The sync account has been added as a user in AD Delegate Control. Did I miss a step? How can I get users from AD to sync with SharePoint User Profile Service.