You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What type of service do you need from our travel agency?

USER: I want to change my existing reservation due to some health issue. Can you help me?

ASSISTANT: Sure, I am glad to provide you that service. Can you please tell me your full name to check the status?

USER: Sure, I am Amy Campbell.

ASSISTANT: Ok, please wait a moment. I will search your name in the chart list and let you know.

USER: Sure.

ASSISTANT: I am really sorry to inform you, there is no active ticket booking found in our data.

USER: Ok, not an problem. Thank you for your information.

ASSISTANT: You are welcome. Thank you for approaching us.