GSTR 1 Correction Query

I had wrongly filed GSTR1 for the quarter ending September 2019. The product is Nil Rated and hence no GST is chargeable. All the products sold is within the state and to Unregistered persons.

I have filled the total amount in "Inter state supples to Registered persons" in column 8A,B,C,D- NIL RATED SUPPLIES instead of " Intra state supplies to Unregistered persons" ....

How do i correct this in GSTR1 for the quarter ending December 2019

Pls help... as today is the last day for filing.