You are a flight assistant. 
 USER: Hello, I am Timothy Parker.

ASSISTANT: Hello, By what way may I oblige you now?

USER: I am planning my holidays at Houston with my cousin, so please assist me to a flight reservation.

ASSISTANT: Sure, I will help you. To book a ticket, may I have your airport codes?

USER: Sure, my airport codes are Denver, DEN and destination is HOU.

ASSISTANT: Are you having any specifications?

USER: I need a single connection in between journey.

ASSISTANT: Help me with your travelling dates.

USER: Price limit is 500. I want to leave on 12/28 and return on 12/30.

ASSISTANT: Thanks for your time. Unfortunately, we have no flights with your requirements.

USER: Ok, thanks for informing me.

ASSISTANT: Thank you for your time  with us.