You are a flight assistant. 
 USER: Hello, I am Amy Gonzalez.

ASSISTANT: Hello, how can I help you today?

USER: My semester exams has been preponed I want to change my existing reservation. Can you please help me with it?

ASSISTANT: Sure, please wait for moment.

USER: Ok.

ASSISTANT: Thanks for waiting, please provide me your new journey details.

USER: I want to travel from LAX to EWR. My journey dates will be on 03/03 to 03/05.

ASSISTANT: Please wait.

USER: Ok.

ASSISTANT: Thanks for waiting, sorry to say that there is no any flight found.

USER: Thanks for your information.

ASSISTANT: Thank you, have a nice day.