You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I guide you?

USER: I am Melissa Edwards. Please help me in changing my recent reservation.

ASSISTANT: Sure, I am here top help you for this. Let me check your reservation status in our database.

USER: Sure.

ASSISTANT: Sorry for inconvenience, no reservation is found with your criteria.

USER: That's ok, no problem.

ASSISTANT: Thank you very much for approaching our agency.

USER: Thank you for checking.

ASSISTANT: You are welcome.