You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you?

USER: Brian Anderson here, I would like to go my sister's home in CLT, so can you find a flight from IAD?

ASSISTANT: Sure, I will find a flight.

USER: Thank you.

ASSISTANT: May I know your travelling dates?

USER: My travel starts on 06/26 and 06/28.

ASSISTANT: Ok, give me a moment.

USER: Ok, I will wait for your response.

ASSISTANT: Sorry Brain, there is no flight found for your required dates.

USER: Oh! It's ok, no problem. Thank you for your services.

ASSISTANT: Welcome. Thank you for approaching us.