New pop-up when I download an app from the App store

Hi, So, all of a sudden, when I try to download an app on my Mac, I get a pop-up (see below) and the app download progress wheel keeps spinning. I tried a different app and had the same result. Any tips? https://preview.redd.it/cyqi1p5cbf9e1.jpg?width=800&format=pjpg&auto=webp&s=d64a0f40c80d672648a003788133a17458098b01