Digital Ocean Apps deployment fails with "Requested runtime 'python-3.9.18' is not available for this stack (heroku-22)

Digital Ocean Apps deployment fails with “Requested runtime ‘python-3.9.18’ is not available for this stack (heroku-22)”

File structure:

├── Diamour_backend
├── Dockerfile
├── authent
├── category_images
├── cloud-sql-proxy
├── cloudmigrate.yaml
├── core
├── db.sqlite3
├── env
├── manage.py
├── requirements.txt
├── runtime.txt
├── static
└── uploads

Runtime.txt:

python-3.9.18

Error message:

2023-10-15T07:47:26.100177307Z │ -----> Using Python version specified in runtime.txt 2023-10-15T07:47:26.340853113Z │ !   Requested runtime 'python-3.9.18' is not available for this stack (heroku-22). 2023-10-15T07:47:26.340887065Z │ !   For supported versions, see: https://devcenter.heroku.com/articles/python-support

Although the documentation for Digital Ocean Apps states that Python 3.9.18 is a supported runtime, I am receiving the error message above when I try to deploy my application. I have checked that the runtime.txt file is in the root directory of my application, and that it contains the correct Python version.

I am using the heroku-22 stack, which is the latest stack available for Digital Ocean Apps. And according the support article from Heroku it does support the 3.9.18 version.

Can you please help me troubleshoot this issue?

Additional information:

• I have tried restarting the Digital Ocean App deployment process, but I still receive the same error message.
• I have checked that there are no other errors in the Digital Ocean App deployment logs.
• I have tried searching for the error message online, but I have not been able to find any helpful solutions.

Related Docs:

• https://devcenter.heroku.com/articles/python-support#supported-runtimes

• https://docs.digitalocean.com/products/app-platform/reference/buildpacks/python/

Thank you for your time and assistance.