In case duplicate TAN has been allotted which TAN should be used?
A23 In case duplicate TANs have been allotted the TAN which has been used regularly should be used. The rest of the TANs should be surrendered for cancellation using “Form for Changes or Correction in TAN” which can be downloaded from the website of NSDL (http://tin.nsdl.com). [Source : http://incometaxindia.gov.