What type of app is it?
There is a difference between the OAuth consent screen settings and your app publication settings.
I believe that you can change/add a scope in the OAuth consent screen, and have it pending approval,
and still have the currently approved list of scopes in effect.
The problem is, if you change a scope and a version number in your publication settings, and save the new settings,
then your live app would probably have a problem authorizing new users, or maybe worse.
If you change your production code file to add the new scope, and have a way to run/test the app without changing your
publication settings in the GCP console, then the app being run in testing/development should ask for the new scope,
and then you can use that to "show" the new permission request.
They often ask for a YouTube video showing the OAuth client ID in the prompt that asks the user to accept the permissions requests.
My experience with getting OAuth scope approvals is with Google Add-ons published to the Workspace Marketplace, so I don't know if my experience is the same as yours.