Andhra Bank — Cash withdrawal without account holder knowledge

Hi, I am a customer from Andhra Bank with the account number [protected] Name: Lalitha Alaparthi In my account my husband death insurance money of 25, 000/- has been credited on[protected] and bank members no one informed on this. When we checked recently and found that from the whole amount 18, 200/- has been withdrawn without my knowledge. And now they are saying bank manager has been transferred. How these employees will withdraw money from my account without my knowledge and Is this the security Andhra bank people are providing to us. I trusted the Bank : Andhra Bank and opened the account but Not that manger or cashier or clerk. Hopw i will get justice on this