The DND sham

I keep getting phone calls from numbers starting with 1409.  Most of them are on "behalf of" Citibank - asking me to take either their credit cards or personal loans.   Ironically I am a Citibank (savings bank) account holder for more than 15 years. 

Since I did not want to take things lying down, I checked if there was a DND (Do not Disturb) facility that Citibank provided.  And would you believe it - they had.  I registered a few weeks back.

If you think that was the end of it, hell, no!  The calls probably stopped for a week or so, but resumed.  

I am back to getting a call per day and have sent a message from my online account.  I am waiting to see how they respond.

What is absolutely disgusting is the call for the same thing from the same people multiple times.  Has there been any study indicating that such tactics help get customers? 

I have nothing against the callers and am sympathetic, but it is hard to maintain composure when yet another call comes in the middle of something important.

For good measure, I have gone ahead and followed the instructions here.  I would think this should be by default.  But then, we are Indian after all and disturbances is a way of life!