India Post — non-delivery of speed post service

Sir
I have to send hard copy of my credentials to the university of warwick ;uk for perusing my phd there. I sent those credentials by speed post on 27 june 2018 vide consignment no. Ej[protected]in. When it remained undelivered i lodged a web complaint on www.indiapost gov.in and given complaint no [protected]. Thereafter daily i am tracking the complaint bit of no help. I have been making calls to various authorities but in vain. I made calls to the kolkata international spc on[protected] but all the time their phone is out of order.
Sir; i have very few days in hand. If these credentials are not delivered my career will get spoiled.
I urnestly request you to take such steps so that the consignment is delivered to the addressee at the earliest. Hoping positively that my career will be saved.