How do I get the roundtrip fare for shuttle?

<p>This is my second attempt to book a shuttle for my D to the airport for winter break and I cannot get it to give me the roundtrip fare even though I’m booking both segments at the same time. It states that the reduced rate will show up at checkout, but when I get to the credit card screen, it wants to charge $80 instead of $60. What am I doing wrong?</p>

<p>When I purchased it, I did get the reduced rate at the payment screen. I have had to contact them on another matter though and found them very responsive.</p>