You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you today from my end?

USER: I am Brenda Martinez. Can you please help me in changing my existing reservation?

ASSISTANT: Sure, I am here to help you out. Please allow me a moment.

USER: Thank you, take your time.

ASSISTANT: Sorry Brenda Martinez, there is no active reservation on your name in our database.

USER: No issues, thank you for your assistance.

ASSISTANT: Thank you for reaching us.