Bajaj Finserv — emi due date was 2nd may and I paid it

Address:	nipani, near vastram, Belgaum, Karnataka, 591237
Website:	money lender

I have paid the emi on the due date, but again i got the message that there is insufficient funds and maintain account balance, and now in statement its showing overdue charges of rupees 450, and i have already paid the emi of 1341 with insurance manually and i have that transaction history, i have the proof but why are they forcing me to pay emi once more with over due charges?

Please tell me how to handle these people