Garage Band not working after an update

Hello Daddyandwilla,

Thank you for posting in Apple Support Communities. We understand that you are trying get garage band on your 2012 Mac. We would love to provide support on this.

The Garage Band app is available in your Mac App Store. If you are unable to download the app it is because the latest version isn't compatible with your Mac OS version. To run the latest version of the Garage Band app your Mac must be up to date on Mac OS Big Sur version 11.0 or higher.

Your Mac 2012 can only up date as high as Mac OS Catalina version 10.15.6.

Thank you for allowing our support community to help.

Have an awesome and productive day!

If you had downloaded it before, go into your account on the App Store and look in your purchase history. Older versions should be there.