You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: My name is Andrew Harris.

ASSISTANT: Glad to meet you Harris.

USER: I have a business meeting in Denver, can you help me for booking a flight ticket?

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

USER: My travelling dates are from 05/03 till 05/05.

ASSISTANT: Ok, may I know your airport codes please?

USER: My travelling airport codes are from SFO to DEN.

ASSISTANT: Ok, hold on for a moment.

USER: Sure, I will wait.

ASSISTANT: Sorry Harris, there are no flights reserved on your requested dates.

USER: That's ok, thank you for checking.

ASSISTANT: Welcome, thank you for choosing us.

USER: Welcome.