You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I aid you today?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, please share your good name?

USER: Melissa Jackson here.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: Thank you for waiting, there is no active reservation found with the given name.

USER: No issues, thank you.

ASSISTANT: Thank you.