You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. Can I know your name?

USER: I am Samantha Mitchell.

ASSISTANT: How can I serve you?

USER: I want to meet my cousin at Denver, DEN. can you please book a ticket for me?

ASSISTANT: Sure, Can I know your travelling dates?

USER: My depart is on 04/24 and return is on 04/26.

ASSISTANT: Do you need any connecting flight?

USER: I need direct flight.

ASSISTANT: May I know your source airport code?

USER: Source code: Detroit, DTW.

ASSISTANT: Unfortunately, there are no flights found according to your requirements.

USER: No problem. Thank you.

ASSISTANT: Thank you for reaching us.