You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I am Betty Campbell. I am planning to travel from DCA to MSP, can you help in finding a flight for me?

ASSISTANT: Sure, may I know your travel dates please?

USER: My date of travelling is on 07/26 to 07/28.

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

USER: That's ok. Thank you for your help.

ASSISTANT: Thank you.