Speed Post — Wrongly delivered letters to other addresses

Address:

New Delhi, Delhi

I applied for PAN card.I got SMS that my PAN card is dispatched on 15/03/2014 by SPEED POST consignment no.EQ[protected]IN.With this consignment no. I track the status of SPEED POST which shows me that on 19/03/2014 the parcel bag is dispatched and on 20/03/2014 received and delivered on the same day but still now I didn't get any letter by SPEED POST.Not handed over me nethier signed by me.
And GOD knows whom received it or signed it?where it is delivered?