Hello RW dvlpmnt,
Welcome to microsoft Q&A, Thankyou for posting your query here.
Check the logs of your container to identify any error message.
https://learn.microsoft.com/en-us/azure/container-instances/container-instances-get-logs
Check your Dockerfile for any syntax errors or to the base image, exposed ports, and start commands.
check if your container is configured to listen correct port and NSG rule is allowed to reach the container.
Ensure that your container is with sufficient resources to support your application's requirements, such as CPU or memory which cause it to fail during startup if resources are insufficient.
Hope this helps you
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