You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you?

USER: I want to book  a flight ticket to attend an event which is going to held at TX. Can you help me?

ASSISTANT: Sure, kindly mention your planned trip dates?

USER: Aug 22nd and 24th are my travelling dates.

ASSISTANT: Do you have any other requirements?

USER: I prefer an normal-cost airline.

ASSISTANT: Can you please assist me with your airport codes?

USER: IAH and HOU are my airport codes.

ASSISTANT: May I know your name please?

USER: Marry Johnson here.

ASSISTANT: Unfortunately there is no flight found with your given information.

USER: No issue. Thank you.

ASSISTANT: Thank you for choosing us.