Blue Dart Express — parcel was returned to sender

Address:

Ludhiana, Punjab

Undelivered shipment held at location (Industrial area sc ludhiana) for seven days and then sent back to the sender by giving reason that the address was incorrect.
However the address was all correct, and land mark was also mentioned along with pincode. Then how it is possibility of incorrect address.

It was very important for me because it contains the study material of my upcoming exam.