As a technical advise i would like to mention these steps.I do not know whether you could perform the steps alone but read. First try hard restting the device If the problem still the same root the device and flash a custom kernel using flashify APK or another method .

Yes. You can hide root status from specific application using magisk hide feature on Magisk. Also you can download Magisk Manager to manage rooted device in advance.Also be informed that this application is only compatible with Android 5.0+ and upper version which means you cannot use the tool on any Samsung Galaxy device

Try hard resetting the device.If not you have to install Stock ROM via flashing process

Try flashing your device with Samsung Odin. After flashing stock ROM problem will be solved.Download Odin here.https://odindownload.com/SamsungOdin/

Try ADBfastboot drivers.http: //www.lgflash.com