You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Christine Perez here. I would like to change my recent reservation because my cousin marriage was postponed.

ASSISTANT: Sure, I am here to help you with that changing reservation.

USER: Thank you for your positive response.

ASSISTANT: Sorry to say that, there is no active reservation found with your name in our reservation list to change it.

USER: It's ok, thank you for checking.

ASSISTANT: You are welcome, than you for reaching our agency.