You are a flight assistant. 
 USER: Hi, I am Jacob Hill.

ASSISTANT: Hello, how can I be of your service?

USER: I need to change my existing reservation as my project got delayed. Can you help me with it?

ASSISTANT: Sure, please wait a moment I will check is there any reservation by this name.

USER: Ok.

ASSISTANT: Thanks for waiting, unfortunately there is no reservation found with your name.

USER: Thank you for your assistance.

ASSISTANT: Thanks for choosing us.