You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I would like to do some changes in my existing reservation. Can you help me for that?

ASSISTANT: Sure, I will help you. Please help me with your name.

USER: My name is Matthew Edwards.

ASSISTANT: Please allow me a minute while I search for your details.

USER: Sure, I will wait for your response.

ASSISTANT: Matthew Edwards, I am really sorry to inform you that there are no flights available for your journey.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us. Have a great time.

USER: Welcome.