You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: Can you help me to change my reservation?

ASSISTANT: Sure, may I know your name?

USER: Sure, my name is Brenda Williams.

ASSISTANT: Thank you. Please wait for a while, let me check your reservation status.

USER: Sure, make it fast.

ASSISTANT: I am sorry, there is no reservation found under your name in our database.

USER: No issues, thank you for your time.

ASSISTANT: You are welcome and have a nice day.