Create API key for v2


I am new to the Rapid 7 apis. I have generated a user specific key from a service account(basically contains all the info). I am able to hit the investigations api /idr/v1/investigations using it. But the same doesn’t work when I hit the v2 apis /idr/v2/investigations.
Also I don’t see the version diffs when creating the api key.
Let know if I am doing something the wrong way.