Delhivery — Parcel not delivered in 10days

Hi, my name is Alisha.
I had to send my pan card documents urgently, so i used express delivery and paid extra for fast delivery. It has been more than 10-15days there is no update, i tried to cancel my shipment but there is an error and I am not able to cancel, I tried contacting customer care but all I get is we will get back to you but nobody has called me and given me correct status of shipment. Those are legal documents which I am sure is lost by now because as I can see the documents have reached delhivery facility on 11th april but delivery to the address is not done by now. Daily the status of delivery is updated to next day but no proper status is provided. I will be taking legal action as the package contained important documents plus I paid for express delivery.