Sorry this happened to you but this stuff happens all the time on both sides the supplier and the buyer.
Things do come up on both sides especially with the buyer who juggles a real world job and the hobby and ofcourse things come up with the supplier also.
This is something that happened to the buyer and he just wants to make other buyers aware.
Now buyers can make a choice of scheduling with so called supplier or not.
No reason to get excited about it.
Smile and be happy