You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Can you help me to change the flight ticket which I had did recently?

ASSISTANT: Sure, I will help you with that. Let me know your name to check your reservation?

USER: Ok, please book a ticket on the name Gregory Scott.

ASSISTANT: Ok, please wait a moment.

USER: Ok, take your own time.

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 choosing us.