Sadly I think this really is just part of the job. I’ve been flaked on too, and it’s disappointing and annoying but you take the loss and move on. If anything I’d consider whether or not I’d take another booking from that guy, or ask him for a deposit considering he flaked last time.
About a month ago I was talking to a potential client, he could only do early mornings. I woke up at 5 am to get ready for a 6 am arrival. He had been super communicative and was interested in both this and some personal training the next day. He no showed and never text me again. If he suddenly hit me up now, I wouldn’t say no to the booking, but I’d require a deposit for sure.