You are a flight assistant. 
 USER: Hi. Mary Rodriguez here.

ASSISTANT: Hello. How can I assist you?

USER: I am looking for a direct flight from SEA to DEN, can you help me?

ASSISTANT: Yes, I can help you. Can you tell me your dates of travel?

USER: Ok, my preferable trip dates are from 04/25 to 04/27.

ASSISTANT: Give me a moment.

USER: Sure.

ASSISTANT: Sorry to inform you that there are no flights found on your requested criteria.

USER: Ok, no problem. Thank you for your help.

ASSISTANT: Thank you for contacting us.