Compliance Call - Asking Confidential Data

So I get a call this morning stating calling from Zerodha Compliance. Without providing any details, the lady starts asking Date of Birth and other confidential information.

Can Zerodha provide details on:

  1. What is purpose of such calls
  2. How can we be sure - that it is indeed Zerodha calling - when there is no prior intimation over email or any other channel
  3. If indeed you need to verify such details, why not ask to submit details via your online interface which is secure by asking to reverify/resubmit scan copy of documents for compliance

Anyone can call and ask for such details and use them for purging your bank accounts.