cannot add action: github webhook

[nick-youngblut]

I'm trying to add a pipeline action, as described at https://help.tower.nf/22.4/pipeline-actions/overview/#tower-launch-hooks. I've filled out all fields in the webform that seem to be required (it would help to identify all required vs optional fields). Still, I cannot add the pipeline action (see attached).

If I switch to "Tower Launch Hook", then I can add the pipeline action. It is not clear why I cannot add the GitHub web hook.

Note: my github repo is private, but I do have added a Github PAT to my nf-tower profile credentials.