Bajaj finance
Wrong ECS to my bank A/C

I have taken a lenovo laptop from Bajaj finance and for which I have to pay 3917/- per month dated on 5th from Dec 08 to 8 months. I paid through ECS on 5th dec & the ECS come to my acct 3 times in Jan. From which on 5th the ECS got cleared and rest 2 bounced for insufficient fund for which ICICI charged me 281/- twice. I have taken the mobile no. of staff to contact from agent and they picked up the phone and handover each other without taking my problem seriously and finally someone told me send your bank statement to my email id. I told him to send his email id into my mobile or my email id but not getting any respose. I am really harrased so much don't know what to do if they send such type of ECS to my acct regularly...