Not sure what environment you are working in, but I believe you have to get the cookie from the GET call and include it in your POST request. This is an example in C#:
As you can see it collects the cookie if it has not already done so. And the cookie collection simply implies running a dummy GET operation:
The real work is done in this method that handles the setup of the requests (that's where the cookie container is configured):
I am working in Qlik script editor.
The documentation doesn't specify anything about a cookie as far as I know.
With the NPrinting api I needed to take part of the cookie returned in the header. This cookie is a lot smaller and I am not sure if this would work.
Also how do I get a post call in the script as I can only create GET calls. So I guess I have to change it with the With connection statement, can't figure out how.
Ill try to just put in the whole cookie.