You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I serve you?

USER: Nancy Taylor here. I want to attend my son's convocation ceremony, so please book my ticket from DFW to EWR.

ASSISTANT: Ok, now please share your travel dates?

USER: My itinerary dates are 03/16 and 03/18.

ASSISTANT: Thanks for waiting. But I am sorry to say that there are no flights available.

USER: It's ok, thank you.

ASSISTANT: Thank you.