Hello @Chandirasekar Thiagarajan,
To address and resolve this issue, we contacted our support team and raised a ticket with the Azure Subscription/Account Review team.
A support engineer from the Azure Subscription/Account Review team will unblock your phone number, allowing you to sign up for a Azure tenant to activate 1 month free trial of Microsoft Entra ID P2 Trial license without any phone validation error.
I hope this above information provided is helpful. Please feel free to reach out if you have any further questions.
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