This client kept was texting me for days with pointless texts saying. You free today? I've told him several times I don't take bookings by text. He texted me again around 12pm:
Him: Hey are you around today?
I ignore his text as it's the millionth time he's asked the same thing but never called me.
Him: I'll call if you are.
Him: Just message me back and I will.
Me: Yes, please call me.
Him: ok, are you around at around 6 or 6:30pm today?
Me: Should be, but please call.
Him: Ok I'll call around 5 pm.
Me: Ok, but I can't hold the booking until you've called me.
He didn't call so I took another booking, then at 5:20pm he texts again:
Him: I'm on my way, will call when I can.
Me: Sorry I took another booking, I did say you needed to call to hold the time slot.
Him: ohh
I mean how stupid is he?

I made it clear he needed to call and he expects me to hold a spot for someone who didn't actually make a booking and wants a non specific time for a slot starting at maybe 6pm or maybe 6:30pm.