Priceline.com uses a Algorithm that when you book a ticket and choose a day and time and go to complete Booking. It will tell you that the flight is no longer available. Then give you a higher rate. When you call the representatives will tell you a even higher rate and try to get you to purchase the inflated ticket price fast.
I used a different computer 5 hours later the same flight was there at an even lower price than when I first tried to book. The Attorney General needs to investigate Priceline.com for fraud.