@Saumya Biswas
Thanks for providing the additional information. My understanding is that you are using a free trial subscription. You should automatically be granted $500 in Azure Quantum Credits when you first launch a Quantum workspace. After 30 days of sign-up or once you've consumed all your Azure Quantum Credits (whichever occurs first), you must upgrade to a pay-as-you-go subscription.
See Create an Azure Quantum workspace for details on how to launch your first workspace and more information on the credits. If you are still unable to launch, you can contact AzureQuantumInfo@microsoft.com.
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