You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you at this moment?

USER: Due to an urgency, I am planning to change my plan to other day, could you change my existing reservation?

ASSISTANT: Ok, I will help you. In my database I did not find any reservation with your name.

USER: My name is Brenda Lee.

ASSISTANT: Anything else to help you Lee.

USER: Thank you for your help.

ASSISTANT: Thank you for contacting us.