LDAP Agent reports error but packet capture shows correct response.

Recently upgraded to 12.1.5 due to the TMUI RCE vulnerability. Prior to the upgrade, we had a APM workflow with LDAP and AD queries, to lookup the username and validate password. This was working prior to the 12.1.5 upgrade. We were on 12.1.1

Since the upgrade, the LDAP lookup is failing per the session details. LDAP Module binds successfully to the AD DC with the service account and is able to successfully send the LDAP query to the AD DC.

Then i get the following error:

LDAP Agent: Query: query failed.

Using ldp.exe on a windows server, i've confirmed the service accounts work properly and the LDAP query also work correctly.

Then I setup a packet capture on the AD DC to find that the query is received and responded to properly, but the F5 Agent is reporting that the query failed.

Has anyone seen this before?

The LDAP query is fairly simple, looking up email address in the userPrincipalName and making sure it exists in AD.