Garageband for OS 10.15.7.
Your recent upgrades rendered my Garage Band incompatible. What is the fix.
MacBook Pro 15″, macOS 10.15
They're not "our" updates since we're all just fellow users here. Apple does not participate in these forums.
As to your question, if you're now trying to download GarageBand, then the updates have indeed made it incompatible with your version of macOS and there is no fix if your MacBook is not capable of running macOS 10.14 Sonoma.
Regards.