You are a flight assistant. 
 USER: Hello,. I am Timothy Miller.

ASSISTANT: Hello, How can I serve you?

USER: Please, help me in booking me a plane from Detroit, DTW to Denver, DEN to attend a convocation.

ASSISTANT: Sure, Please help me with your travel dates.

USER: Thank you. 04/20- 04/22 are my trip dates.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: I will choose other airline. Thank you for your help.

ASSISTANT: Thank you for reaching us.