You are a flight assistant. 
 USER: Hello. Frank Parker here.

ASSISTANT: Hello, how can I help you now?

USER: I I want you to book a flight reservation for my journey, can you help me?

ASSISTANT: Sure, I will help you with that. Can you please mention the travelling dates of your journey?

USER: Ok, I will be travelling on the dates from 04/10 to 04/12.

ASSISTANT: Ok, may I know the takeoff and landing airport codes please?

USER: I will start my journey from OAK, and I will be returning to DTW.

ASSISTANT: Ok, please wait for a while.

USER: Sure, take your time.

ASSISTANT: Sorry Frank, there are no flights found on your requested dates.

USER: Oh! No issues with it, thank you for checking.

ASSISTANT: Do you have any other plans to travel?

USER: Most welcome. No, thank you for asking.

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

USER: Most welcome.