HTC — Sound system,

Dear sir, I have ordered HTC desire 816, duel sim recently from EBAY ONLINE.I waited for its delivery but it is delayed and i left my hostel(Gulbarga) for 1 and half month for an academic course in Shillong..in my absence, (after 4 days, i left the station It is received by my friend.I came back two days back and its been my second day that iam using my new HTC. Now im totally depressed and sad because the smooth conversation has become highly impossible. I here the voice of the person who calls me but my voice is not reaching to to those who call me.whats wrong with me. I have paid 15000 rs with much difficulty. And aim not able to use my new phone even to make a call. whats the use of this new cell. Why its doing like this in only a second day. and music, song sound is also very irrittaing..no use of the cell only on second day. its too bad. I need another set. kindly help me. i struggled a lot to buy this new phone, provide me another hand set plz plz plz as soon as possible. how should i provide photo proof for this problem?