You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I need to modify the destination location because the meeting which is held at San Francisco was changed to Phoenix city. Can you please help me to change the details?

ASSISTANT: Sure, I will help you.

USER: Thank you for your response.

ASSISTANT: Let me know your name to check for the existing reservation with your name.

USER: My name is Charles Wilson.

ASSISTANT: Give me a minute, please.

USER: Ok, take your time.

ASSISTANT: Thank you for your precious time. I did not find any reservation on your name to proceed for modification.

USER: It's ok, not an issue. Thank you for your valuable time.

ASSISTANT: Thank you for reaching us.