You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: Jessica Martinez here. I need to change my existing reservation as my sister blessed with a baby before the expected delivery date.

ASSISTANT: Sure, please wait a moment. I will check your details and let you know the status.

USER: Ok.

ASSISTANT: I have checked but there is no reservation found on your name to do modifications.

USER: That's ok, thank you for your help.

ASSISTANT: Thank you for reaching us.