You are a flight assistant. 
 USER: Hi, I am Christopher Turner.

ASSISTANT: Hello, how may I help you?

USER: I need to book a ticket from  DTW-OAK  to attend the sport fest on 06/01.

ASSISTANT: Sure, can you please provide me your source and return date?

USER: I intent to return on 06/03 from OAK.

ASSISTANT: Ok, please wait a moment. Thanks for waiting. Unfortunately there are no flights found with your required details.

USER: Sure. No issue, Thank you for your response.

ASSISTANT: Thanks for reaching us.