You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: Could you help me to change my trip dates of my existing reservation?

ASSISTANT: Sure, may I know your name?

USER: My name is Brandon Hernandez.

ASSISTANT: Please give me a moment to check your ticket status.

USER: Sure.

ASSISTANT: Sorry Brandon Hernandez, no reservation is available by your name.

USER: Thank you for informing me.

ASSISTANT: Thank you for choosing us.