Iphone 12 pro shuts down unexpectedly

Hello everyone,

I own a iphone 12 pro. The last couple of months it's been shutin down and won't start up unless you plug the charger or wireless charge. I noticed that it's more probably when it is around 50%. Yesterday I had the phone working and when I tried to open an app (no matter which) it shuts down and if you press the power on it will start once open the main screen shuts down immediately. The only way is the charging way. The battery is been replaced twice, to avoid the possibility of a faulty new battery, it went for a repair but with no luck.. any ideas?