Managed Metadata terms changes display name is reflecting . Taxonomy Update Scheduler is not working

I am using Terms in list publish using Managed metadata services. I required to do Change certain terms . its Changed successfully.

I open the list where i am using it , its update as display only, when i use custom code to fetch the term its still showing the previous name. 

i verify the Taxonomy Update Scheduler from timer services , its running without any error, but somehow its not updating the values.

There is hidden list for taxonomy  that is need being update automatically, 

Need to update the Hidden list using powershell with below script.

$siteUrl = "http://devvmspap01:15734/"
$site = Get-SPSite $siteUrl
[Microsoft.SharePoint.Taxonomy.TaxonomySession]::SyncHiddenList($site)
$site.dispose()