Beginner Needing help with boolean element in Unity

I’m a complete noob when it comes to Unity. I’m following a guide on making a card game in Unity just to get my bearings. I’ve got to a part in the guide where we’re making a card back and it can be toggled on and off with a UI element in unity (see below). For some reason when I run my program I can’t click the UI element to make the card back appear.

Any help would be appreciated.

Could you please share the code?

Open the DisplayCard script by double click on it (in the Inspector) and look for cardBack or something boolean think, and what logic connected to it.