You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you today?

USER: I am Susan White. Owing to an emergency, I want to change an existing reservation. Could you help me in changing reservation?

ASSISTANT: Sure, we are here to help you. Please wait a minute, I will check your reservation in the database and let you know.

USER: Sure.

ASSISTANT: Thank you for being patient, sorry to say that no reservation matches with provided name.

USER: Not an issue. Thanks for your information.

ASSISTANT: Thank you for opting us, have a nice day.