India Post — service and misbehaving

Address:

117/716 Q Block, Sharda Nagar Kanpur, 208025

This is complaint against postmanand postmaster of 208025 naveen nagar kanpur u. P
Sir, i m a resident of sharda nagar kanpur. One of my close friend who is handicap and live six months before with us, now she is working out of city. Her one certificate came via registered post. Which was not handover to me. Instead i am saying to show authorization letter to postman but he said she should come with i. D to post office. Next day when she met to postmaster than he refused to deliver to her. Just because of i was submitted a complaint letter. Now they return back her registered post to bhopal.
Is it valid and sufficient reason to return back a registered letter?
Now postman behave very rudely and today again he is not deliver a letter.
Please see this issue and resolve.
Please provide me guidelines for above matter which help me to avails your services. Thanks you.