@SharathKumar A - Welcome to Microsoft Q&A and thanks for reaching out to us.
It's possible that you are trying to create a virtual machine that is not included in the free services available with your Azure free account. The Azure free account provides a limited quantity of free services for 12 months and a set of services that are always free. However, not all services are available for free, and some services have usage limits. For example, the free account only includes access to one type of VM for free - the B1S Burstable B series that's usable for up to 750 hours per month.
To avoid charges, ensure that you create resources from the Free services page. And then when you create a resource, be sure to select the tier that's free.
Hope this helps. and please feel free to reach out if you have any further questions.
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