You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how could I aid you today?

USER: I am Thomas Edwards want to change my reservation due to prepone of my meeting. Can you help me with it?

ASSISTANT: Sure, please wait for a while.

USER:  Ok.

ASSISTANT: There is no reservation found with your given name.

USER: Thank you for your help.

ASSISTANT: Thank you for choosing us.