You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What can I do for you?

USER: My name is Gregory Martinez, owing for an emergency I would like to change my reservation. Can you help me?

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: No reservation found on your name Gregory Martinez.

USER: No problem, thank you for checking.

ASSISTANT: You are welcome.