Environment settings aren't being applied

[gavinclarkeuk]

Problem Description

When modifying settings.yml on an existing repo to add environments the environments aren't being created. It seems to work for brand new repos.

environments:
  - name: new-env

What is actually happening

Nothing

What is the expected behavior

A new Environment is created (with approvers as defined)

Error output, if available

Context

Are you using the hosted instance of repository-settings/app or running your own?

Hosted instance

If running your own instance, are you using it with github.com or GitHub Enterprise?

N/A

Version of repository-settings/app

Not sure how I can tell the version of the hosted instance

Version of GitHub Enterprise

Again not sure how I can tell, we have an enterprise account at github.com