Filter on User not working for get method in 7.6.2.1

Hi ,

I am having SugarCRM with version as  Enterprise 7.6.2.1 build 9 , along with this i am using rest v10 API to search data in my custom application.

For this specific instance only filter only on User Module is not working  for get Method. While when i excuted count url for the user is working. Filter on rest of module like contact, account  working great.

here is my get method url as follow:

https://192.168.100.154/SugarEnt-Full-7.6.2.1/rest/v10/Users?filter[0][user_name]=abc&offset=0&order_by=date_modified:AS…

Though this instance don't have any records of user_name= abc its returning me the default user list

While same is executed on other sugarCRM instance (with same version or different) , its working fine by retrieving proper output.

Please let me know what may be possible root cause of these issue.