You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Richard Walker.

ASSISTANT: How may I assist you?

USER: Can you aid me in rescheduling my existing reservation?

ASSISTANT: Sure, I will help you. Let me check your reservation status.

USER: Take your time.

ASSISTANT: Sorry Walker, I did not find any reservation under your name in our database.

USER: No issues. Thank you for checking.

ASSISTANT: You are welcome and thank you for reaching us.

USER: You are welcome.