Filing of revised return for A.Y.2018-2019

From AY 2018-19 onwards, a revised income tax return can be filled at anytime before the expiry of the relevant assessment year or before completion of the assessment, whichever is earlier.

The last date to file the revised return with respect to assessment year 2018-19 is March 31, 2019

You could have revised till 31.3.2019. Now you can not revise, however if you have received defective return notice then you can file to rectify mistake

As per the section 139  sub section (4) of the Income tax act 1961 ,  Last  date  for filing  revised  return for  F.Y 2017-18 A.Y 2018-19  was 31/3/2019  .