Make sure to select the ‘Return Period’ for which you want to import the file. You can fill GSTR-9C & generate JSON only using the Desktop App. If you’ve logged in via ClearTax GST website , a modal will pop-up, asking you to continue filing GSTR-9C through the ClearTax GST Desktop App. Click on ‘Open ClearTax GST Companion’ to continue filling the form.