Permission issue for the admin account to remove a member from project area using API

Our automation working with APIs to automate removing members of the project areas when a user is terminated from the Organization. We have provided JazzAdmin access for the account which is used to remove the members of the project area and we have tested manually using web client, we are able to remove the members of the project area. But when we are using the API to identify the user and remove the user we see below error. Please let us know what is the difference between deleting manually and API and the cause of the permission error. 

EWM server: 7.0.2 SR1

Database: SQL

FYI, we are using below API

http://%Host%/%Getenvironment%/process/project-areas/%ProjID%/members/%UserID%

Error 403

CRJAZ6053E To complete the 'Project areas' task, you need these permissions: 'You don't have permission to perform the following actions:
  Modify collections of team members (modify/members)'
CRJAZ2676I Details about the error were written to the log file. To find this data, search the log file for this identifier: 89f3453a-c8ac-4c8b-8f53-d39f380d74db.

com.ibm.team.process.common.advice.TeamOperationCanceledException: CRJAZ6053E To complete the 'Project areas' task, you need these permissions: 'You don't have permission to perform the following actions:
  Modify collections of team members (modify/members)'
  Name: Project areas
  ID: com.ibm.team.process.server.saveProjectArea
  Severity: ERROR
    Summary: Permission Denied
    Description: You don't have permission to perform the following actions:
  Modify collections of team members (modify/members)
    Severity: ERROR

Thanks,

Vinay