Change of bill date in gstr1

sangeeta (Accountant) (63 Points)

05 January 2022  
in gstr1, bill dated 01-07-2020, 01-08-2020, 01-09-2020 were put as 07-01-2020, 08-01-2020, 09-01-2020 in the return of July, aug, sept 20, how can the same be rectified? can the supplier get credit of ITC of those bills? till what time ITC can be utilised? any supporting documents available for the same? any provision in gst law?