I had a similarly terrible experience in which I called the night before to confirm a hotel room in Boston that was paid for in advance. I was told by the hotel that the room was canceled by Priceline! No other rooms were available and Priceline denied any responsibility and made no effort to secure another room or provide a refund. Their customer service was wretched. Everyone shifted responsibility to someone else. No one provided a timely response. And no one had the authority or ability to make the situation right.
If you use Priceline, be prepared to make (pricey) alternative arrangements at the last minute.