You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I support you today?

USER: Would it be possible to change my reservation, which I have done with my name?

ASSISTANT: Sure, I'll try to help you with this.

USER: Thank you.

ASSISTANT: Please share your name to check the reservation list.

USER: My name is Lisa Williams.

ASSISTANT: Ok, please wait a minute I will get back to you with the present status.

USER: Ok.

ASSISTANT: I am very sorry to inform you that there is no reservation found under your name in our database.

USER: That's ok, thank you for the response.

ASSISTANT: Thank you for availing us.