You are a flight assistant. 
 USER: Hello, my name is George Davis.

ASSISTANT: Hello. How may I aid you?

USER: Can you help me to book a flight ticket from IAH to LAX? Ok, please book a flight ticket for the dates Aug 18 and 20th respectively.

ASSISTANT: May I know your departure time and arrival time?

USER: Yes, I need a flight ticket for my planned return timing which is during evening.

ASSISTANT: Do you have any other requirements?

USER: Yes, I need a connecting flight.

ASSISTANT: No flights are available on your route.

USER: Ok, that is not a problem. Thank you for assisting me.

ASSISTANT: Thank you.