Issue when uploading video on Vimeo (through my iOS app)

I am facing issue when uploading video from iOS application on behalf of other users.

Steps are below:

1. In Vimeo, I logged in with my company account and created Vimeo app.
2. After that I sent a request to Vimeo for Upload scope.
3. Then my app approved for Upload scope, and I have client_id, secret_id, redirect_ui, etc..

MyApps: https://developer.vimeo.com/apps

Then, I was following OAuth flow, for that I am opening following url in mobile app browser:

https://api.vimeo.com/oauth/authorize?response_type=code&client_id=XXX&scope=upload&redirect_uri=XXX&state=XXX

but I am getting following error:

An error has occurred. You won't be able to connect to Vimeo until it is fixed by the developer. Dear app owner, we are unable to generate access tokens using one or more of the scopes you provided.

If anyone faced this issue, let me know the solution. Also let me know if any other detail needed to rectify this issue.

from Issue when uploading video on Vimeo (through my iOS app)