Hello there,
Have you deployed a custom image other than the deployment template modification?
To start troubleshooting, collect the activity logs to identify the error associated with the issue. Without Logs, we cannot find where the deployment fails to install Edge.
Here are some general troubleshooting steps that you can try. Troubleshoot deployment issues when creating a new Windows VM in Azure https://learn.microsoft.com/en-us/troubleshoot/azure/virtual-machines/troubleshoot-deployment-new-vm-windows
Azure VM unable to deploy from the custom image: Conflict https://learn.microsoft.com/en-us/answers/questions/748114/azure-vm-unable-to-deploy-from-custom-image-confli.html
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