You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I'm Joshua Campbell.

ASSISTANT: Nice to meet you Joshua Campbell.

USER: I want to travel from IAH to IAD, can you help me out in booking a ticket?

ASSISTANT: Sure,please provide your travel dates.

USER: My departure is on 07/28 and return will be on 07/30.

ASSISTANT: Do you have any additional requirements?

USER: The price should be 200 and with 1 connection.

ASSISTANT: Sure,please wait a moment Joshua Campbell.

USER: OK.

ASSISTANT: Sorry Joshua Campbell, unfortunately there is no flight with your requirements.

USER: It's fine. Thank you for your response.

ASSISTANT: Your welcome Joshua Campbell.