You are a flight assistant. 
 USER: Hello. My name is Frank Hill.

ASSISTANT: Hello, how may I help you at this moment?

USER: I want to do some changes in my existing reservation, can you please help me for that?

ASSISTANT: I will surely help you. Can I have a moment to check the status?

USER: Sure. take your time.

ASSISTANT: Sorry Hill, no tickets is showing on your name in our records.

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

ASSISTANT: Yes, it might be. Thank you for reaching us.

USER: Welcome.