You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Charles Miller here.

ASSISTANT: Can you please tell me how may I guide you?

USER: Can you help me to book a flight ticket from SFO to HOU?

ASSISTANT: Sure, I am gleeful to guide you with the ticket booking. Could you please mention your planned travel dates?

USER: My planning dates are 11/25 and return on 11/27.

ASSISTANT: Ok, please let me check the flight availability.

USER: Sure.

ASSISTANT: Sorry to inform you that, I have not found any flight in this route on the dates you have given.

USER: That's ok, thank you for checking.

ASSISTANT: You are welcome. Thank you for reaching us.