You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I need you to book a flight ticket from EWR to IAH, please help me.

ASSISTANT: Please help me with your travelling dates?

USER: December 5 and 7 are my planned travelling dates.

ASSISTANT: Is there any connection limit?

USER: I need a break in my journey.

ASSISTANT: Do you have any other requirements?

USER: I wish to return in the evening.

ASSISTANT: May I know your good name?

USER:  My name is Helen Mitchell.

ASSISTANT: Sorry to inform that, there is no flights found with your required dates.

USER: That's ok. Thanks for your time.

ASSISTANT: Thank you for choosing us.