It may also be noted that there is no concept of revision of a filed return under the GST regime. However, the details furnished in Forms GSTR-1 and GSTR-2 which have remained unmatched as per Section 42 or 43 can be rectified as and when the error or omission is discovered. However, no rectification is permissible after filing the annual return or the return for the month of September of the following year (whichever is earlier).
(ICAI FAQ PUBLICATION 06-09-2017 -: Returns : FAQ NO. 9)