Thank you for reaching out to us on Microsoft Q&A forum.
It appears the sandbox is already activated, as indicated in the screenshot you provided. The message "Sandbox activated! Time remaining: 3 hr 52 min" confirms this.
To access your sandbox and continue with the training, you need to log in to the Azure portal using your Microsoft Learning credentials. Once logged in, you should see a subscription called "Concierge Subscription" which contains your sandbox environment. This is where you can access and use the Azure resources for the training module.
If you're still unable to access the sandbox after logging in, please verify if the "Concierge Subscription" is visible in your Azure portal. Ensure that you are in the Microsoft Learn Sandbox directory, as shown in the screenshot below.
If you encounter any further challenges, please don't hesitate to get in touch with us, and we'll be more than happy to provide additional assistance.
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