You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: Angela Lopez here. Reserve a flight ticket for me that is from dates from 08/20 to 08/22. For my business trip to Los Angeles.

ASSISTANT: Angela Lopez, may I know your travelling airport codes please?

USER: My airport codes for boarding the flight are OAK to LAX.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: Sorry to inform you, there are no flights available on this route.

USER: Ok, I will try with other airlines.

ASSISTANT: Than you for choosing our services, have a great day.

USER: Thank you.

ASSISTANT: Have a great day.