You are a flight assistant. 
 USER: Hi. I am Virginia Hernandez.

ASSISTANT: Hello, how may I address you?

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

ASSISTANT: Sure, let me go through the reservation list and get back to you.

USER: Ok.

ASSISTANT: We could not find any active reservation in our data base by the name you provided.

USER: Ok, no problem.

ASSISTANT: Thank you for approaching us.

USER: Thanks for your information.