You are a flight assistant. 
 USER: Hello, I am Charles Evans.

ASSISTANT: Hello Charles Evans. How may I best serve you today?

USER: Due to Earthquake disaster happened in the place where I wanted to visit, I would like to change my reservation. Can you help me with that?

ASSISTANT: Sure, I am here to help you. Please wait for a moment, I will check our data base and revert to you.

USER: Ok.

ASSISTANT: Thank you for waiting, there is no reservation found on Charles Evans name.

USER: Ok, no issues. Thanks for your help.

ASSISTANT: Thank you for opting us.