Wallet arrived broken. What is this kind of knob/clasp called so I can order another?

This wallet arrived with a random screw that wasn’t connected to anything. I’m assuming it was supposed to be the button to clasp it. The company is taking forever to get back to me about a replacement. I’m trying to order a similar clasp that would fit that has a backing but I don’t know what it’s called. Can anyone help me on the name of what I’m looking for?