Season 6, Episode 17: "The Kiss Hello"

Oh, hi, Mr. Costanza. We were trying to get in touch with you.

Wendy can't make her appointment.

-What do you mean? -She had some personal affairs...

...she had to attend to.

I left a message on your machine. You didn't get it?

-When did you leave the message? -A few hours ago.

Oh, I'm sorry. I require 24 hours' notice for a cancellation.

Now, as I see it, you owe me $75.