Related to Ipcc marksheet

Help me in this case:
My marksheet had come to my place via post but no one was present. So dey dropped a note on which my name n address was written rest I was not able to understand. On the note it was mentioned 23/08/18.i went yesterday as I didn't have time to go to post office. And the staff said that it is almost a month now your document might have been sent back to the sender. He was sure about this. Now, how will I get my original marksheet, any idea?