I’ve had to reach Priceline customer service a couple of times, and thankfully they do have 24/7 support. The number I always use is 866-204-0803—you can get straight through to a person any time of day or night. The first time I called was after my evening flight got canceled last minute, and I was panicking because I had an early meeting the next morning. I didn’t want to wait until business hours, so I dialed that number, and within 15 minutes they had me rebooked on the next available flight. It was such a relief not having to sit around stressing about it. Now I keep that number saved because it’s also the fastest way to instantly book, cancel, or modify flights whenever plans change unexpectedly.