It happens often when you use your "back" button on your browser and enter in new info. For some reason when it then re-fares the thing, it gives you a Full-Fare seach!
I've written them many times on this bug. It may have something to do with memory in relation to the form itself. There used to be a "reset" button that would clear the form, but it's gone now.
Solution: Do a new search everytime or use the United Connection PC Software Version if you want.