They have a dedicated booking person and they are having scheduling problems like this? wooow, that's nice !!
When I make an appointment I always tell them my name (nickname of course) "Hi, this is Jack, can I see Anna at 7pm". When I arrive they almost never verify my name. Sometimes they ask me if I called and sometimes they don't even ask me that. I don't break my routine and say "Hi, this is Jack. I called earlier to see Anna at 7pm". Now, you might think this would help to avoid scheduling/waiting problems? yeah, not as much as we think. I am not specifically talking about Healthy Spa, I'm talking about all Spas. I waited 15 mins at Sunflower not long ago; besides they weren't busy at all. Call me sceptic but I don't believe Anna took the walk-in because she thought it was you, she took him because he was a client, ready to go and right in front of her.