You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I serve you?

USER: Owing to emergency, I need to change my recent reservation. Please help me in that.

ASSISTANT: Sure, may I know your name please?

USER: My name is David Young.

ASSISTANT: Wait a moment.

USER: Ok.

ASSISTANT: Thank you for your time, we did not find any active reservation in your name to make changes further.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for reaching us.