how two way communication is possible between agent and customer using rest api

[Sidheshwar Sai]

Our company is working on a project where we want that our customer can comment on particular card through our portal  i.e. we want two way communication can be done between agents and customer, where customer can comment through our portal. How we can achieve this. I have used oauth2.0 also.  from there I am getting access token but when I am commenting using this It is giving "Issue does not exist or you do not have permission to see it"

[Nic Brough -Adaptavist-]

Welcome to the Atlassian Community!

This is what it says it is - the user your REST call is logging in as does not have permission to see the issue or it does not exist (Or your user is not authenticated, and anonymous access is off, so you have to log in to see issues)