You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Thomas Taylor here.

ASSISTANT: How can I help you today?

USER: I'm planning to visit Houston tourist attractions in this winter, can you please book me a ticket?

ASSISTANT: Thomas Taylor, can you tell me your travelling dates for this trip please?

USER: Sure, my departure date is 01/04 and return date is 01/06.

ASSISTANT: May I know your airport codes also?

USER: My airport codes are SFO and IAH.

ASSISTANT: Sorry Thomas Taylor, no flights are currently available for you.

USER: That's ok, thank you for your service.

ASSISTANT: Thank you for reaching us.