Hi @Rudrani Bhadra ,
As per the offline discussion, your ADB workspace is part of your Visual Studio Subscription (Free Azure Credits) and since you have reached the monthly cap for your free credits, your Azure services will stop until your next monthly credits are added unless you choose to remove the spending cap by upgrading to pay-as-you-go pricing.
This is the reason why you were not able to delete any resources in your Visual studio subscription. To explore more about visual studio subscription free credits please refer to this doc - Use Microsoft Azure in Visual Studio subscriptions
Hope this info helps.
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Thank you
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