Catalina Security update 2021 003 10.15.7 I try to download it twice and my computer wouldn't restart

It downloads and then the computer restarts itself. It runs for about 3minutes and the bar going across under the apple ID gets stuck. I can't hit the start button it's done automatically

I'll give it a try.

It worked, I did the shutdown and restart and then I downloaded the security update 10.15.7 and it worked. Thank you very much.

Thanks again.