Consultant in finance department

I was met with the worst attitude from a staff member by the name of Althea working in the finance department. My call was related to a query regarding my Chubb business account and banking details which had not been changed as requested. She had the worst attitude I have ever experienced with a consultant over the phone. After questioning me about whether an email with the updated details had been sent, she then discovered that they had in fact recieved the email and that "someone in joburg" had recieved the email and not updated it as requested . I then proceeded to ask her (Althea) why she could not do it for me instead as she had the original email infront of her with the new banking details. She then told me that she could not because she needed me to send a new email to her email address. At this point I had already been annoyed with her stinking attitude and unprofessional behaviour (she kept asking me to hold on while shouting in the background to her colleagues about my request and my email which she had infront of her) She then proceeds to question my authority is a very condescending manner, abruptly asking me "who are you" in a rude tone, repeating this several times and thereafter putting the phone down in my face. I am so utterly disgusted in her behaviour. Since when is it allowed for staff members to speak to clients in this manner? People like this are the reason for companies losing valuable clients. She should be dealt with or I will cancel my membership