GSTR 1 IFF FILING PROBLEM

I have uploaded GSTR 1 IFF DETAILS FOR THE MONTH OF FEB 2021 ON 13.3.2021.  BUT UNABLE TO SUBMIT DUE TO ERROR IN FILE.  NOW WHILE FILING MARCH RETURN INCLUDING FEB NVOICES IT SHOWS FEB DATA ALREADY UPLOADED.  HOW TO DELETE FEB 21 DATA UPLOADED BUT NOT FILED.  OR CAN I UPLOAD ONLY MARCH DATA IN MARCH AND FILE GSTR1. WHETHER WILL PORTAL ACCEPT FEB AND MARCH DATA AS RETURN FILED.  PL CLARIFY HOW TO FILE FEB 21 AND MARCH 21 RETURNS UNDER QRMP IN APRIL 13TH LAST DATE. Urgent