Hello @Koushik Ganguly - Thank you for reaching out to us!
From the details provided, I see that you have an Azure Pass subscription with 2 days left for expiry and want to leverage the remaining balance by adding your credit card - meaning by converting the offer to Pay-As-You-Go (PayG). Currently, this is not possible - You cannot use the remaining balance if the Azure pass period is over, same goes with the Free trial as well.
For example: If you upgrade your Azure Pass subscription to PayG, you will be able to use the remaining credits for next 2 days, post that you will be billed as per PayG rates. The advantage of upgrading to PayG before expiry date, ensures availability of services.
Hope this answers your question. Please reply if you have further questions in this matter!
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