The CBIC has notified the Notification no. 58/2020- Central tax dated 1st July 2020 in which rule 67A has been notified which says about the manner of filing of Nil return of GSTR 3B and GSTR 1 through SMS. The taxpayer shall have to file the Nil return through sending SMS from the registered mobile number.
To view and download the notification, click here NN 58-2020