In one of the GST Returns filed in FY 2017-18, GST Number of 1 buyer has been wrongly reported 
in GSTR-1 (Party Name was same, but GST Number of its branch in another state.)
As a result the invoice is not getting relected in GST 2A of correct buyer.
Now GST R-1 of Oct 18, has been already filed.
When I checked from different sources, it is written that it is not possible to amend GST No. in GSTR-1 whether any update has been provided by GST WEBSITE regarding this limitation.
Can GST No be amended in invoice of FY 17-18
If not what should be the remedy.