GSTR9 (F.Y.2020-21)

Our Annual Turnover for the F.Y. 2020-21 is 1.87 Crore So GSTR 9 Fillup for the F.Y. 2020-21 is mandatory, Optional or Exempt ?
because  we see that as per notification 31/2021, Dt. 30/07/21 is written hereby EXEMPTS the registered person whose Aggregate Turnover in the F.Y. 20-21 is upto 02 Crore rupees, from filling Annual Return for the said financial year.