You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I am John Martin.

ASSISTANT: Nice to meet you.

USER: Can you please book me a ticket from DCA to DEN to meet my friends?

ASSISTANT: Sure, will you mention your travelling dates please?

USER: I would like to leave between on 06/08 and 06/10.

ASSISTANT: Please give me a moment.

USER: Ok.

ASSISTANT: Thanks for waiting, there is no flights found under your preferable details.

USER: Ok, no problem.

ASSISTANT: Thanks for reaching us, have a great day.

USER: Thank you.