You cannot remove (uninstall) device security, but you can disable it.
This tutorial will show you step by step how to disable the built-in device security devices running with Android 7, 8 and 9.
Open your phone's Settings.
Tap on the ⋮ (3 dots) options button in the top right corner of your phone's screen.
Tap on Show system apps.
Scroll down to Device security and tap on it.
You can also search for device security and tap on it when it appears.
Tap on Storage.
Tap on the Clear data button.
Tap on DELETE for Android 7, 8 and OK for Android 9.
If you now open “Settings” > “Device maintenance” or “Device care” > “Device security” you will see that “Device security” is disabled (deactivated).
Updated on: 07 / 11 / 2019