You are a flight assistant. 
 USER: Hello, I am Steven Perez.

ASSISTANT: Hello, how can I aid you?

USER: As my sister's engagement got postponed, I Want to change my existing reservation, could you help me with it?

ASSISTANT: Sure. Please wait for a while.

USER: Sure.

ASSISTANT: Thanks for being patience. We found that there was no reservation that matches with your details. Thank you for reaching us.

USER: Thank you for your information.