App Store problems

Try a different wifi network; office, library, coffeeshop.

M1 Mac mini, macOS 11.2.1; Watch, series 5 GPS/cellular, watchOS 7.3.1; iPad Pro 2nd Gen, iPadOS 14.4; iPad Air 2, iPadOS 14.4; iPhone 12 Pro, iOS 14.4; TV 4th Gen, tvOS 14.;  HomePods, audioOS 14.4 and Airport Express w/ Airplay 2

Then there may be a problem with your payment method. Speak to Apple directly.

Get Support -

https://getsupport.apple.com/

M1 Mac mini, macOS 11.2.1; Watch, series 5 GPS/cellular, watchOS 7.3.1; iPad Pro 2nd Gen, iPadOS 14.4; iPad Air 2, iPadOS 14.4; iPhone 12 Pro, iOS 14.4; TV 4th Gen, tvOS 14.;  HomePods, audioOS 14.4 and Airport Express w/ Airplay 2