Thank you @nathan.loding,
Connector is working fine after giving the correct permissions for operate API , Apologies Previously gave permissions for different one
I have tried the operate and tasklist API’s and by giving the Authorized oauth token as header in postman
Operate API is working only if we give the { "audience":"operate-api" }
in the body as mentioned here
where as Tasklist API is working fine without any audience as tasklist-api
@Ingo_Richtsmeier what is the importance of specifying audience?