You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Emma Johnson here, my exams has been preponed I want to change my reservation. Can you please help me with it?

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry, no reservation found with your name.

USER: Not an issue, thank you.

ASSISTANT: Thank you for opting us.