Issue
Your Heroku account or Team has been deleted for non-payment of invoices, and you'd like to see if it's possible to recover the contents.
Resolution
Heroku requires your Team or Personal Heroku account to remain in good standing, with up-to-date credit card information. If your account falls into a past due or delinquent status, Heroku will suspend and subsequently permanently delete your account. This will only occur after an ample ~30+ day grace period and multiple email notifications to Account Owners/Team Admins.
If your Heroku Personal or Team is deleted for non-payment, the account and apps (particularly the app code and config vars) no longer reside on Heroku, which means we are not able to recover them. Database backups may exist for Heroku Postgres at the Standard-0 (production tier) and above, for up to 10 days after the account is deleted and under certain provisions. To learn how to recover a database backup, you can review this article:
Can I recover a deprovisioned production (non-Hobby/Mini/Basic) Heroku Postgres database?