You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: My name is Sharon Hall, can you help me to change the reservation which I had done last week?

ASSISTANT: Sure, we re here to help you. Please wait a moment I'll check the reservation list.

USER: Ok, please take your time and thank you for the positive response.

ASSISTANT: Thank you for waiting, I have checked in reservation list to change your ticket, but could not find any reservation with your name.

USER: That is ok, thank you for assisting me.

ASSISTANT: Thank you for approaching us.