For September GSTR-3B filing a technical failure occurs on the GST portal on the last date of filing. In the past 6 six days, the GST portal has been challenging technical issues, and various people are complaining about the issues on Twitter.
October 31 is the last date for filing the GSTR 9 & 9C 
CBIC again extended the due date of GSTR 9, 9A and 9C for FY 2017-18 till 31st December 2019 and FY 2018-19 till 31st march 2020 for the FY-2018-19. The businesses whose turnover exceeds Rs 500 cr is mandatory to file the GST along with e-invoicing from October 1. Infosys manages the portal, where technical failure has happened which causes #gstnfailed to trend on Twitter.
The GST official account handler has answered some of the complaints asking the people to complain again if the issue gets repeated. GSTN said on October 18 states that a total of 27.4 lakh GSTR-3B have been filed so far for September 2020.
GSTN portal 
Read out the complete guide of official GST return filing portal i.e. GSTN for Indian taxpayers. We explain all the important part with the brief introduction is the one destination for all the taxpayers assessees and the GSTN officers where they connect and go through all the relevant transactions, GST filing records and can contact on the basis of it for further resolutions.
on GST portal while filing gst 3b for nov.2020 – pending all return i done with late fee also.
but on GST portal file return dashboard 2020 -21 not seen in dialog box
PROBLEMS ARISING AT THE TIME FILING GSTR-3B, the LAST STEP OFFSET SUCCESSFUL
DOES NOT PRINT, WHAT WILL WE DO?
Please refresh the page again or clear the browsing history