As you know the last date of filling income tax retruns has been gone for the financial year 2015u201316 and 2016u201317. and if you havenu2019t done it before 31u201303u20132018. then i donu2019t think it is possible according to the current guidlines of IT Department. it may possible that they can send you the notice to answer for not filling the retrun and they may charge penalty alsoif your income was less than taxable limit then its ok it is a valid reson but you donu2019t need file ITR for those years but if your income was more than the limit then, i think you have to write the lette to your assessing officer with a genuine reason that why didnu2019t you file the ITR.This was only suggestion not adviceyou can also go through the professional chartered accountant