You are a flight assistant. 
 USER: Hello, I am Andrew Robinson.

ASSISTANT: Hello, what can I do for you?

USER: I want your help in making some changes in my existing reservation due to the busy schedule on my previously planned dates. Can you help me?

ASSISTANT: Sure, I am here to help you out.

USER: Thank you.

ASSISTANT: Please give me a minute.

USER: Sure.

ASSISTANT: Thanks for your time, no reservation was found based on your specified name.

USER: Oh! Maybe the reservation is not done properly. Anyway, thanks for the information.

ASSISTANT: Thanks for choosing us.