What you show looks correct, but clicking the “More” should show the API call’s captured fields. Because it shows blank, it suggests the API call didn’t get initialised with a sample set of result data.
I remembered that I faced a similar situation with another plugin earlier. So what I ended up doing is removing the whole call and publishing a new version of the plugin and then adding it again under a different name.
The problem seems to start when I duplicate a call in the plugin editor. So if anyone else faces a similar problem remember to delete publish and add again!