Through the Heroku PostgreSQL add-on create a new backup capture you can do that by the UI or the CLI running:

heroku pg:backups:capture -a your-production-name-app

and after that run:

heroku pg:backups:restore <production-database-name>::<you-backups-id> DATABASE_URL --app <production-staging-enviroment> --confirm <production-staging-enviroment>

example:

heroku pg:backups:restore juanequex-prod::b194 DATABASE_URL --app juanequex-staging --confirm juanequex-staging

Enjoy! c: