Hi Shrikant Bhagwat,
Based on your query,
The user needs to check their access to subscriptions in the Azure Portal to ensure they have the right permissions, like Owner, Contributor, or User Access Administrator. If they don’t have access, they’ll need someone with admin rights to grant them the correct role through Azure Role-Based Access Control (RBAC).
Please refer the below document for more information
https://learn.microsoft.com/en-us/azure/role-based-access-control/built-in-roles
And also confirm the logged into the correct tenant in Azure Portal sometimes, users might be in the wrong directory, which can prevent Cloud Shell from detecting the existing subscriptions.
Another key thing to check is whether Cloud Shell has a storage account set up. Cloud Shell requires an Azure Storage Account within the subscription to function properly, so they should verify that one exists or create one if needed.
Please refer below document for more information
Get started with Azure Cloud Shell using persistent storage
Before using Azure Cloud Shell, register the Microsoft.CloudShell resource provider in your subscription via Azure Portal > Subscriptions > Resource Providers. If it’s unregistered, click Register, and Cloud Shell should work fine as per below document
Get started with Azure Cloud Shell
Instead of using Microsoft Admin Center, it’s best to try accessing Cloud Shell directly from Azure Portal by clicking on Cloud Shell in the top bar. If it opens normally, the issue is likely related to Admin Center access rather than an actual subscription problem.
And also refer the on-Cloud Shell troubleshooting provides additional guidance
https://learn.microsoft.com/en-us/azure/cloud-shell/faq-troubleshooting
There are relevant discussions in the community Q&A where users have faced similar problems the answer it might help to your resolve your issue
https://learn.microsoft.com/en-us/answers/questions/200610/unable-to-launch-cloud-shell-asking-me-to-create-n
If you have any other query, please let me know just ping me in comment
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