You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you for today?

USER: Christine Collins here.

ASSISTANT: Ok.

USER: I want to book a ticket for seeing my grand father he is not feeling well, will you help me on that?

ASSISTANT: Sure, I will help you with that. May I know the airport codes and the travelling dates of your journey?

USER: My airport codes are from HOU to PHL. I would like to travel on 05/12 to 05/14.

ASSISTANT: Ok, please wait for a moment.

USER: Make sure connection limit should be 1 with in the price 500. Sure.

ASSISTANT: Sorry for the inconvenience, there are no flights found on your requirements.

USER: Ok, no problem. Thank you for your help.

ASSISTANT: Thank you for contacting us, have a great day.