Hi Shankari S,
Thank you for reaching out to us on the Microsoft Q&A forum.
To resolve the issue of upgrading to the Developer plan under Azure sponsorship, ensure that all the information in your Azure account profile is complete and accurate, including your credit card details, and confirm that there are no conflicts with another Microsoft account using the same information. If the issue persists, you can submit a support request through the Azure Portal by navigating to Help + Support and creating a ticket for further assistance. Alternatively, you may also open a support ticket via the Founders Hub for additional help.
Please open a support ticket with the Founders Hub support team by following these steps: https://foundershub.startups.microsoft.com/signup?drawer_open=true please click on "Support" on this page to submit support ticket.
Please reach out to us if you have any other queries.
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