Error 502 Bad Gateway when deploying into ACI

I followed the tutorial for deploying this app in Azure Container Registry but tried to launch the app with Azure Container Instance (with a Linux machine). The deployment went well but when reaching the site, I got a 502 error.

Do not really know if I made a mistake or if this is due to the code itself.

Start by reproducing the tutorial deployment with Azure Container Registry and Azure Container Instance on Linux, then inspect the deployment and application logs around the 502 response. Compare the working tutorial configuration with the reported setup; done means identifying whether the failure is in the app or deployment and documenting a confirmed fix.

Written by the indexing model from the issue text.