You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: Elizabeth Clark here. I am planning to travel from EWR to OAK to attend my sister's marriage. Can You help me for booking?

ASSISTANT: Sure, may I know the travelling dates?

USER: My trip dates are 07/06 and 07/08.

ASSISTANT: Sorry, there is no flight found.

USER: It's ok.

ASSISTANT: Thank you.

USER: Welcome.