You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: My name is Samuel Jones. Can you help me to book a flight ticket from SFO to IAH?

ASSISTANT: Ok, please provide your travelling dates to search for the flight?

USER: Ok, please can you book for the dates Aug 15 and 17 respectively?

ASSISTANT: Do you have any particular time for departing and returning?

USER: Yes, please can you book for the departure timing during morning and arrival timing is during afternoon.

ASSISTANT: Are you looking for any specific airlines to travel?

USER: No.

ASSISTANT: Sorry, there is no flight is available for you on your route.

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

ASSISTANT: Thanks for choosing us.