The Goods and Services Tax Network (GSTN) has issued following advisory on Annual Return (GSTR- 9) on February 24, 2021:
The taxpayers are advised to ensure that values are reported upto two decimal places in the GSTR-9 offline utility. The error “Error! Invalid Summary payload” after uploading the JSON created from the Offline Utility of GSTR-9 is reported due to reporting values upto three decimal places instead of two decimals.
Source from: https://www.gst.gov.in/newsandupdates/read/454