DTDC Courier & Cargo — Consignment missing/stolen

I had booked my courier containing a watch worth rupees 3000/- via DTDC service on 11th Nov 2016 with docket no Z02164148 to Hyderabad.
As per the online tracking details courier had reached Gachibowli (hyderabad) on 14th Nov and till date it's status is "In Transit ".
They did not ask me about the content while i was handovering the packege to them and later on claimed that i should have pre informed them about it.
According to the DTDC service as i was couriering an electronic product without pre informing them, consignment is stuck at investigation level and will be delivered in few days.
After few days they informed me that consignment is misplaced and could not be tracked, hence could not be delivered.

I am unable to lodge official complaint against them, as none of their customer care number is responding.