itdesk REST API: always getting invalid ticket

itdesk REST API: always getting invalid ticket

Hello,

 I"m creating a script for bulk loading the worksheet into Service Desk Plus (cloud version, the one at https://sdpondemand.manageengine.com/).

 Using my everyvday user I've created a Self Client at the developer console, I use it to get the authorization code and then HTTP POST this information at https://accounts.zoho.com/oauth/v2/token. I got the access and refresh tokens sucessfully.

 Now, when I try to get a ticket or a ticket list, I always get this:

{'response_status': {'messages': [{'status_code': 4001,
    'type': 'failed',
    'message': 'INVALID_TICKET'}],
  'status': 'failed'}}

 I've tried both https://sdpondemand.manageengine.com/app/itdesk/api/v3/requests and https://sdpondemand.manageengine.com/api/v3/requests. If I try this very same URLs at my browser (logged into SDP), I get the ticket list.

 What did I do wrong?

Thanks,
Max