Hello.  I need to find a flight.  Can you help me?
Where are you departing from?
San Francisco.
Where are you going to?
I am off to Detroit.
On what day do you want the plane to arrive?
I have a flight ID in mind can I just give that to you?
Sure, we can do that.
Flight ID is 639.
May I have your name, please?
Yes I am John.  
Sorry, but the flight with id '639' is not available any more.
Well that's not good.  Can we check the weather in Detroit?
For what day would you like the weather forecast?
Saturday please.  
It will be Cloudy all day on Saturday in Detroit, with temperatures of around 6 degrees celsius.
That doesn't sound too bad.  Ok let's try that flight again if you don't mind.
Sorry, but the flight with id '639' is not available any more.
Can you try one more time?
Sorry, but the flight with id '639' is not available any more.
It is an emergency I really need to get on that flight.
Sorry, but the flight with id '639' is not available any more. Would you like me to find another flight?
Well I need something from San Francisco to Detroit.
On what day do you want the plane to arrive?
The 9th please.
Unfortunately there are no flights that match your search. Would you like to change any of your criteria?
Can you try to find me something close to that date?  This is what I get for waiting until the last minute I guess!
Right, I found an Economy flight with American for 234 credits
 that takes 7 hours to get to Detroit.
That will work.  Thank you for finding me something!
Sorry, but the flight with id '95' is not available any more.
Can you try again?
Sorry, but the flight with id '95' is not available any more.
Well I have to book a flight so if you could find me something close to that date it would be wonderful.
I'm sorry, but your reservation request was unsuccessful.
Ok well I guess I will try some other time then.  Thank you for the help.
Is there anything else that I can do for you?