Bajaj Finserv — bajaj finserv collection team

Address:	Kolkata, West Bengal, 700084
Website:	www.bajajfinserv.in

My name is moumita chakraborty. My customer i'd is 48075121. I have one running personal loan which is converted from retail emi. My running loan account number is[protected].
Emi is deducted through ecs from my bank account which is sbi.
For running loan i made bank account change request to one of bajaj loan collection employee who came to my place for taking the missed emi. The person who came to my place and did all the necessary things for changing the bank account details was sent by a bajaj employee whose name is priyanka (Mobile-[protected]).
They did nothing and for past 2months my ecs is bounced and i have been charged rs.600 for bouncing charge. For this my cibil score has been decreased.
I made the request and give 2 cancelled cheque of kotak bank and also signed mandatory ecs form on 9.2.2018.
I don't know why such thing is happening. Bajaj collection members are making me fool and for their fault i am suffering. Whenever i told them that i will pay the missed emi through online but they do jot hear me and continuously calling me and harrassed me.
If they can't do this from themselves they should tell me directly to do this by myself.
I want proper justice to this. Kindly look into this matter.
I want a written document for this solution and assurance from bajaj finserv that such thing will not be happened in future.