You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Can you please help me in booking my flight from IAD to reach PHX?

ASSISTANT: Sure, may I know the planned travel dates please?

USER: My travel dates are May 7th and May 9th.

ASSISTANT: Is there any connection limit?

USER: I prefer a single connecting flight.

ASSISTANT: May I know the class preference?

USER: I don't have any more specifications.

ASSISTANT: May I know your name?

USER: My name is John Roberts.

ASSISTANT: John Roberts, I regret to inform that there are no flights on the specified routes with the given dates.

USER: Ok, not a problem. Anyways, thanks for the information.

ASSISTANT: Thank you for reaching us.