You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Catherine Hernandez.

ASSISTANT: How can I aid you?

USER: I need to change my existing reservation, can you please help me with that?

ASSISTANT: Sure, we are here to help you. Please wait a while.

USER: Sure.

ASSISTANT: Thanks for your time. We didnt found any reservation by this name.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for contating us.