GSTR 3B WRONG VALUES ENTRY

HI all,

while  filing Gstr3B for the month of November 2017 we made huge mistake by filing the same sales and purchase values of previous month ( of October 2017).

so please guide us how to rectify it,(we filed correct GSTR 1 for November)

how we can adjust remaining values of sales and purchases in  while filing Gstr3b of January month,can we add remaining values with January month sales and purchases or add in other tiles(sections)

with Regards

kulkarni