@Focus DevTeam Thank you for posting your question in Microsoft Q&A, apologize for any inconvenience caused on this.
As mentioned in the above logs, could you please enable the diagnostic logging and review the container logs/ log stream logs of the app service to troubleshoot/understand the issue and also add this application setting "WEBSITES_CONTAINER_START_TIME_LIMIT" = 1800 as well.
You can also make use of WebApp Down detector under Availability and performance in Diagnose and solve problems of you webapp for initial troubleshooting.
Hope this helps, let me know if you have any further questions on this.