Hi @Mathanagopal,
When you upgrade from a free trial account to a Pay-As-You-Go (PAYG) account in Azure, you move from using limited free services to a billing model where you pay for the resources you consume.
The B1S VM is an affordable option, but it is still a paid resource. Once you created this VM after upgrading to PAYG, charges began to apply for its usage.
If you have any further queries, do let us know.
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