You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am Gregory Perez. I need to visit Houston, IX - IAH. Can you please book a flight ticket from San Francisco, CA - SFO?

ASSISTANT: Sure, we are here to help you. Can you share me your travelling dates for booking purpose?

USER: 01/26 and 01/28 are my travelling dates.

ASSISTANT: Do you need any halt or direct flight in between your journey?

USER: Yes, I need a halt.

ASSISTANT: Ok, wait for some time I will check the availability of flights and get back to you.

USER: Sure, I will wait.

ASSISTANT: Thanks for your precious time. Unfortunately there is no flights your requested details.

USER: Ok, no issues. Thanks for your information.

ASSISTANT: Thanks for approaching us.