You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What can I do for you at this moment?

USER: Due to some entrepreneurship meeting, I am going to change my existing reservation. Can you please help me in changing the reservation?

ASSISTANT: Sure, may I know your good name please?

USER: I am Charles Thomas.

ASSISTANT: Ok, please wait for few minutes.

USER: Sure.

ASSISTANT: There is no existing reservation found on your name in our records.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us.