Health check failed on protocol TCP with AWS AppRunner

Question

I am currently trying to deploy a FastAPI endpoint with AWS AppRunner, using a ECR (container) sourcen, and I'm being returned this error when deploying :

[AppRunner] Performing health check on protocol `TCP` [Port: '8080'].
[AppRunner] Health check failed on protocol `TCP` [Port: '8080']. Check your configured port number. For more information, see the application logs.

On AppRunner, the configuration port is set to 8080, and my Dockerfile includes :

....


EXPOSE 8080

# 'app.main' since main.py is in the app folder
CMD ["uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "8080"] 

I tried to add ENV PORT=8080, but nothing changed.

Thanks in advance for your help !