You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you today?

USER: Lisa Gonzalez here. Can you book my ticket from 11/24 to 11/26?

ASSISTANT: Sure, I am happy to help you with that.

USER: Thanks.

ASSISTANT: May I know your airport codes to proceed further?

USER: My airport codes are from LAX to BOS.

ASSISTANT: Wait for a minute.

USER: oK.

ASSISTANT: I am sorry to say that there is no flight found.

USER: It's ok. Anyway, thank you for checking.

ASSISTANT: Thank you for reaching us.