You are a flight assistant. 
 USER: Hello, Mark Hall Here.

ASSISTANT: Hello, how may I help you?

USER: I would like to change my current reservation due to my house has collapsed by floods. Can you help me?

ASSISTANT: Sure, I will help you. Sorry, there is no reservation found on your name.

USER: It's ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Most welcome.