Vegas Effect not showing up

Hi everyone!

I've been loooking at YouTube tutorials on how to apply different effects in AE as I'm new to this program, and I'm having an issue with applying one of the effects the vegas one, despite doing everything as shown in the video.

In my project, I have added a solid layer grey square to my white background, and dragged the vegas effect on to it (a red triangle appeared on the square), but the yellow dots are not appearing around the edges of the square as they should be. This has meant none of the alterations to segments, hardness, etc. are doing anything and I can't go further with the video tutorial I am watching.

Can any of you see anything I am doing wrong or suggest something that might need to be enabled?

I have attached a screenshot of my project.

Thank you 🙂