You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I would like to celebrate my birthday at San Francisco, please help me in booking a ticket from PHL to SFO.

ASSISTANT: Sure, may I know your travelling dates?

USER: My planned travel dates are on Apr 26 and Apr 28.

ASSISTANT:  On which name shall I reserve flight ticket?

USER: My name is Karen Evans.

ASSISTANT: Do you need any specifications?

USER: I prefer a connecting flight.

ASSISTANT: Please wait.

USER: Sure, take your time.

ASSISTANT: Sorry, there are no flights found on given dates.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Thank you for reaching us.