The MRV fee is usually valid for a period of one year from the date of payment. In a welcome measure, the U.S. Mission to India has notified that they will extend the validity of the visa application fees until December 31, 2021 even if the one-year validity is completed prior to that. 

The U.S. mission has also indicated that they are working to restore all routine visa operations, keeping it as safe as possible.

This update can be found here.