This article was created in response to a support issue logged with K2. The content may include typographical errors and may be revised at any time without notice This article is not considered official documentation for K2 software and is provided “as is” with no warranties.
System Values still shows the old Manager for the user after modifying it on AD.
This is the expected behavior since the System Values don't depend on K2 and they are dependable on the Account information. This information gets cached in the LSALookupSID cache on the server.
The right information will be shown soon after the cache gets cleared. If this is not the case, the cache can be cleared by running the powershell script to clear it:
$objUser = New-Object System.Security.Principal.NTAccount "mydomain\"
Here is the complete KB Article: https://support.microsoft.com/en-us/help/946358/the-lsalookupsids-function-may-return-the-old-user-name-instead-of-the