Hi Narasimha Reddy Krishnareddygari,
Thank you for reaching out to Microsoft Q & A forum.
There is currently an issue with sandbox activation, and our internal team is actively working on resolving it. In the meantime, you can use the workaround below to complete your exercise.
You should be able to work around the issue by first Activating the sandbox (solving puzzles, reviewing permissions, etc.) and then once you see the sign-in box appear on the right open a new browser tab. In this new tab, browse to https://shell.azure.com. If your existing sandbox hasn't expired you can use that instead of activating a new one.
When prompted, click Bash
Next choose No storage account required, for Subscription select Concierge Subscription, and click Apply.
After several seconds delay while a cloud shell is requested and connected to, you should see $ prompt. At this point you can complete the exercises instructions, copy/paste code from exercise tab to cloud shell tab as needed, etc.
Additionally, you should be able to open a separate browser tab with the Azure portal to complete your exercise seamlessly.
Please feel free to contact us if you have any additional questions.
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