How to get refund if 26as has been corrected

I am a pensioner from Osmania University Hyderabad. I filed my returns ITR 1 for AY 2016-17  on line on 7th April 2016, since I was visiting US and thought that earlier the better. At that time26As obtained from ITvwebsite was showing Tax deducted as Rs 42526 with certain income.This was the case even about 15 days ago.  My returns were processed and  approved and I received 143/1 yesterdy by email.  when I casually checked up 26AS now, this shows higher income and additional tax.  What should I do now for additional income and additiona Rs 11000 tax deducted?  What is the procedure since 143/1 is received?