Punjab National Bank [PNB] — Activate auto loan deduct service without my permission

Address:

Meerut, Uttar Pradesh, 250106

Dear sir/madam, i have take a loan of rs two lakh in pmmy in oct 16 my installments starts from jan 17 i deposit my installment on regular basis but manager activate the sim service without my permission after this i talk him about this than he says i will deactivate this but he don't and now he says this is not possible to do so.
i deposite my installment before due date and after this they deduct another installment in same month from my saving account.