You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Melissa Thompson.

ASSISTANT: How may I help you today?

USER: My scheduled examination dates has been postponed, could you please help me with changing my recent reservation?

ASSISTANT: Melissa Thompson, let me check with your previous booking for a moment.

USER: Sure, take your time.

ASSISTANT: I am so sorry to inform you but there is no flight reservation available by your name.

USER: That's ok, not an issue.

ASSISTANT: Thank you for choosing us.

USER: Anyways, thank you for the information.

ASSISTANT: Have a nice day.