You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I am Karen Clark, can you help me to booking a flight on 07/16 and 07/18?

ASSISTANT: Sure, could you please let me know the source and destination airport codes.

USER: My airport codes are AUS and PHX.

ASSISTANT: Sorry Karen, there are flights found on the give schedule.

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

ASSISTANT: Thank you for contacting us.