REMEDY FOR MISTAKE IN FILLING OF GSTR1

DEAR SIR, 

I AM A GTA SUPPLIER AND ISSUED BILL OF SUPPLY TO RECEIPIENTS, BUT DURING THE FILLING OF GSTR 1,  SOME ENTRY OF B2B MISS  TO MARK AS ''ATTRACTING RCM'' WHILE SAME ENTRY SHOW IN GSTR 3B AS EXEMPTED SUPPLY,  NOW DEPARTMENT RAISE DEMAND FOR THOSE INVOICES TREADTED AS SUPPLY IS UNDER FCM AND TAX HAS NOT BEEN DEPOSITED BY ASSESSEE ? 

WHAT IS REMEDY FOR ISSUE ?