Bajaj Finserv — wrong finance done by bajaj executive

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L-1ST, 1738/5, SANGAM VIHAR, NEAR BY ASTHAL MANDIR, New Delhi, Delhi, 110062

As i want tell you tell around three years ago i gave my document to bajaj executive regarding to finance a second hand phone so instead of second hand set he financed a new handset and took my sign on papers and all. Now it's comes to know that he done the finance of a new handset and gave me the old handset which value is one fourth of the new handset. Now bajaj is asking for the money so what i have to do? I am helpless.