You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: I want to change my reservation, can you help me with that?

ASSISTANT: Sure, let me know your name to check further?

USER: Please check it on the name of Andrew Johnson.

ASSISTANT:  Sorry, no reservation found on your given name in our database to change it.

USER: Ok, no issues. Thanks for the help and support.

ASSISTANT: Thank you for contacting us.