You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: I am Cynthia Edwards. I am planning to change an existing reservation, due to some urgent work. Can you please change my ticket?

ASSISTANT: Ok, give me a moment to check with your reservation.

USER: Sure,  I will wait.

ASSISTANT: So sorry to inform you, there is no reservation found in our data base by the name of Cynthia Edwards.

USER: That's fine.

ASSISTANT: Thank you for reaching us for your help.

USER: Thank you for your service.

ASSISTANT: Most welcome.