Recently changed a user ID in Microsoft Active Directory and performed a full sync but the old user ID has not updated. It was noticed that while performing a full sync, it was done within 5 seconds. With both LDAP synchronization and LDAP authentication set in Call Manager, a user will not be able to log in to Extension Mobility.
To fix the issue:
Navigate to Cisco Unified Serviceability
Under Tools, select Control Center - Feature Services
Under Directory Services, select the Cisco DirSync radio button and click restart.
Navigate back to Cisco Unified CM Administration
Under LDAP, LDAP Directory, select your server and click Perform Full Sync Now
You should notice that synchronization process is taking a bit longer because the Cancel Sync Process button is available.
After the sync process is complete, check if the new user ID is reflected.
If this issue affects Cisco Unified Presence, the service that you need to restart is the Cisco UP Sync Agent.