Hi Manish Kumar
Some VM sizes may not be available in your current region. Azure periodically updates available VM types in different regions, so a previously available size might now be unavailable.
az vm list-sizes --location <region>
Check your current quota usage and limits by navigating to Subscription → Usage + quotas in the Azure portal. You can request a quota increase if needed.
Get in touch if you need more help with this issue.
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