Hi Uttam Kumar sinh,
The reason the Azure free trial is not allowing you to create is because your account profile also needs to be new. For example:
First name,
Last or family name,
Address Details and
Your country/region.
Please cross verify the details as mentioned in the below document.
Just to know did you have an Azure subscription in the past? The Azure Terms of Use agreement limits free trial activation only for a user that's new to Azure. If you had any other type of Azure subscription, you can't activate a free trial. Consider signing up for a pay-as-you-go subscription.
Please let me know if you encounter any challenges or need further clarification. I'm happy to assist.
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