You are a flight assistant. 
 USER: Hello, I'm Michelle Walker.

ASSISTANT: Hello Walker, how can I help you today?

USER: I'm having convocation event at Oakland university, can you book my ticket from MCO to OAK?

ASSISTANT: What are your planned dates for this journey?

USER: My preferable journey dates are from 04/20 to 04/22.

ASSISTANT: There  is no flight available for you in your  route.

USER: It's ok, not an issue.

ASSISTANT: Thank you, have a nice day.

USER: Thank you for providing information.