You have to authorize first.
Navigate to
Admin → External Applications → Add new Application → Give a name(Swagger) → Add Scopes → Select Orchestrator API From drop down (Add all Application scopes)
Save it then you will get appid and app secret in a pop up…
Copy the app secret
Go to swagger file click on Authorize and paste the app secret in client secret field
then you can use api cals
cheers
l