GST sales wrong

karthikrao (B.com CS(inter) -ongoing)   (170 Points)

31 July 2019  
Sir, I wrongly entered Debtor one local sales instead of IGST sales in Nov 18 and filed GSTR 3b on same month.Since I want to reverse it and to be shown as correct sales.Kindly tell me a Entry to be reverse it and put it on IGST sales nw