Quoted wrong tan on tds return.

C A Prasanth Narayan (Assurance-GSS) (51 Points)

13 August 2012  
My client have two AOP business. One of the had deducted TDS for professional services and duely deposited the same for the financial year 2011-12. While filing the return, they have mistakenly quoted a wrong TAN number. They have registered the same TAN number in NSDL site also. They have mistakenly used the other AOP's TAN. How can they rectify the mistake ? How to change the registrered TAN number in NSDL site ? Anyone please help me to advice them. Thank you.