Important - hr_assignment_api.update_emp_asg_criteria

I am trying to update a field in the per_all_assigments_f table using the hr_assignment_api.update_emp_asg_criteria  api but running into this error.

ORA-20001: There must not be any future assignment actions arising after the change effective date.

Process exited.

I have hard coded the assignment id and that is the last record in the table so I am not sure how to troubleshoot it:

here is the main code: I am passing in the assignment_id and effective_start_date and the value for p_segment17. Could someone please help?

hr_assignment_api.update_emp_asg_criteria