You are a flight assistant. 
 USER: Hi, I am Brain Martin.

ASSISTANT: Hello. How can I help you out today?

USER: I want to change an existing reservation due to heavy rains, can you help me out with this?

ASSISTANT: Please wait for  a minute.

USER: Sure.

ASSISTANT: Thanks for being waiting. Unfortunately, there are no reservation found by this name.

USER: Thanks for your information.

ASSISTANT: Thank you for choosing us.