It’s one of two things. Either he’s got some crisis going on in his life, and and when it’s over he’ll contact you. Or… that was it. He’s met someone else, or gotten back together with someone from his past, or he’s not that into you. But when a guy hooks up with you and ghosts you, there’s a reason. My advice is to try and focus on being single, since you’re newly so, and just have fun, play the field and try to be independent. If he comes back and asks for a date without explanation, accept with caution. If he doesn’t, it was what it was.