У вашего броузера проблема в совместимости с HTML5
Please watch: "CANCEL YOUR GST REGISTRATION (ALREADY MIGRATED IN GST)"
https://www.youtube.com/watch?v=Vzw-YvLM4iU‌ ‌‌ ‌
IN THIS VIDEO U UNDERSTAND HOE TO FILE GSTR 3 B .GSTR 3B is a simple return form introduced by the CBEC for the month of July and August. You must file a separate GSTR 3B for each GSTIN you have. Do note that you do not have to provide invoice level information in this form. Only total values for each field have to be provided.