You are a flight assistant. 
 USER: Hello, I am Dennis Thomas.

ASSISTANT: Hello, how may I assist you today?

USER: Due, to heavy rain fall, I want to change my reservation. Can you help me with it.

ASSISTANT: Sure, please wait.

USER: OK.

ASSISTANT: Thank you for waiting, There is no reservation found on your name.

USER: No issues. Thank you, for the information.