Tibber.com API call - help with authorization.

Hi.

I'm trying to reach my electricity company through their public API.

I'm able to use the POST field in the command to get a response but a layer of authorization is required.

Is anyone able to point me in the right direction on how to incorporate the authorization token in my call?

This call gives me a response (from their examples)

call:

{
"query": "{ viewer { name }}"
}

response:

{"data":null,"errors":[{"message":"No valid access token in request","locations":[{"line":1,"column":3}],"path":["viewer"],"extensions":{"code":"INTERNAL_SERVER_ERROR"}}]}

Documentation:

https://developer.tibber.com/docs/guides/calling-api

Any help is appreciated