You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Mary Martinez.

ASSISTANT: How can I serve you for today Mary Martinez?

USER: Owing to emergency, I need to change my existing reservation. Please help me with that.

ASSISTANT: I am glad to help you about that Mary Martinez.

USER: Thank you.

ASSISTANT: Please wait for sometime to check the reservation status with your name.

USER: Ok.

ASSISTANT: I apologise to say this Mary Martinez, there is no active reservations with your name in our booking list.

USER: Nothing to worry. Thanks for letting me know.

ASSISTANT: You are welcome, thank you for reaching us.