macOS Mojave App Store won't sign in
I brought MacBook Pro (15-inch, 2018) just 2 days ago. I tried hundreds of time to login to App Store (I want to download Xcode).
I can logged in in iTunes, but in App Store credential dialog moves up just like logging successful but actually not.
I tried everything explained here (https://discussions.apple.com/thread/8554285 ), but nothing works.
App store works fine in my iPhone XS with my Apple ID.
OS up to date (macOS Mojave 10.14.3), and restarted many times.
I had a very bad first experience with Apple.
MacBook Pro 15”, 10.14