Claim of income tax refund

I have filed a belated income tax return of an individual assessee for the financial year 214-2015 on 14.07.2016 but inadvertently forgot to claim the T D S OF RS.3500/-. Consequently, REFUND OF rs. 3500/- was also not claimed in the return. Kindly note that I am also not able to file the revised return since it is a belated return.My assessee wants to claim the refund. Kindly help.