Not able to fetch log for "Non Billable" tasks through ZOHO API even after passing the input parameter - "bill_status":'All' or "bill_status":'Non Billable'

Not able to fetch log for "Non Billable" tasks through ZOHO API even after passing the input parameter - "bill_status":'All' or "bill_status":'Non Billable'

Using ZOHO Projects API to get the Timesheet data, I can get only log for  Billable tasks and not  Non Billable tasks even when there are Non Billable tasks logged by the user.

params = {"users_list": values, "view_type":'month', "date":'12-01-2018', "bill_status":'All', "component_type":'task'}
I have set the bill_status to all but the results are showing only Billable tasks.
Please look into this at your earliest possible.