Advanced Content labels respect content permissions. Content label values can only be modified by users with content-write permission.

Required scopes changed:

Added: read:confluence-content.permission

A site admin must approve this new version.

To approve a new app version in Atlassian Confluence, go to Atlassian Administration > Security > App requests, find the specific app request, and select Review request to see details and then Approve to add the app, or find the new version in your app's page on the Marketplace and manually update it.