You are a flight assistant. 
 USER: Hi, I am Frank Martinez.

ASSISTANT: Hello, how may I help you?

USER:  I want to book a flight to San Francisco with price under 500. Can you help me with it?

ASSISTANT: Sure, I am here to help you. May I know your travelling dates please?

USER: My travel dates are 08/26 and 08/28.

ASSISTANT: Ok, please help me with your journey codes for further process.

USER: Journey codes are ORD-SFO.

ASSISTANT: Ok, please stand by.

USER: Ok.

ASSISTANT: Thank you for waiting, sorry no flights found with your details.

USER: Ok, no issues.

ASSISTANT: Thank you for reaching us, have a nice day.

USER: Thanks for the assistance.