You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: George Gonzalez here.

ASSISTANT: How can I assist you?

USER: Previously I have done a reservation in my name, due to my sudden promotion I want to change my existing reservation. Will you help me?

ASSISTANT: Sure, I will help you that. But give me a moment I will check it.

USER: Ok.

ASSISTANT: I am sorry to say that there is no reservation found on your name.

USER: It's ok, fine. Thank you for checking.

ASSISTANT: Thank you for contacting us.