Thanks for your response!

That all makes sense - I have run into that a lot before. I was just confused because it takes me to the united website, where the price is shown the same as it was on google flights. Usually for me if it is just a google flights creation, when I go to the airlines website the price has changed or is no longer available. I guess this is a first for me where the price on google flights is the same as on the airlines actual website, but then it is not bookable through the airline.