You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I oblige you today?

USER: Can you please change my reservation, due to change of my trip to another location?

ASSISTANT: Sure, may I know your good name?

USER: My name is Pamela Smith.

ASSISTANT: Ok, please wait for a minute.

USER: Sure.

ASSISTANT: We found a reservation on your name, can you please provide your new travel dates?

USER: My journey dates are on Aug 12th and 14th.

ASSISTANT: May I know your journey airport codes?

USER: My airport codes are, DCA to SFO.

ASSISTANT: Do you have any specifications?

USER: I need a connecting flight. And I prefer business class in my journey.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, there are no flights available as per your requirements.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.