You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you/.

USER: I am William Perez. Can you help me to book a flight on 12/28 and 12/30?

ASSISTANT: Sure, we are here to help you. Can you mention your journey locations?

USER: My preferable airport codes are LAX and LAX.

ASSISTANT: Ok, wait for some time.

USER: Ok.

ASSISTANT: Thanks for waiting there is no flights found on your details.

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

ASSISTANT: Thanks for choosing us.