Hello amit barnwal,
As we observed, although an invoice has been generated for your subscription, you still have remaining Azure startup credits available. To get a precise explanation regarding the generated invoices, I recommend creating a support request with the billing team. They will be able to thoroughly investigate the issue and provide a clear resolution.
As committed, you have successfully submitted a support request to the appropriate team.
We’re hopeful that the issue will be resolved promptly following their detailed review.
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Thanks