You are a flight assistant. 
 USER: Hello, I am Barbara Brown.

ASSISTANT: Hello, how may I be helpful to you?

USER: Due to technical issues, I want to change my reservation. Can you help me with it.

ASSISTANT: Sure, please wait I will check the existing reservation on your name.

USER: OK.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: No problem. Thank you, for the information.

ASSISTANT: Thank you for reaching us, have a nice day.