India Post — consignment not delivered yet

Address:

New Delhi, Delhi, 110007

I posted a letter to chandigarh from delhi (Jawahar nagar po 110007) on 7/12/18 (Ed[protected]in). On checking the tracking status it showed that the consignment has been despatched for palam tmo on 8/12/18, but till today it hasn't even reached palam tmo.
It was promised that it wilk get delivered in three days but it has been a week and not a clue. So please help me and get it delievered as soon as possible.