You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I aid you?

USER: I am Frank Carter, I need to change my reservation as my schedule got postponed to some other day.

ASSISTANT: Sure, I will help you with that.

USER: Thank you for your positive response.

ASSISTANT: Sorry, we didn't found any reservation under your name in our database.

USER: It's ok, anyway thank you for the information.

ASSISTANT: Thank you for reaching us.