Unity Crashes when trying to create pre-installed system app on android device

We are trying to make a pre-installed system app on customized android device. When we are installing it as normal app, it works fine but when we try to push it in system folder it crashes with error "Unable to find native library :main"

We have tried to manually copy the .so files to system/lib folder and giving it 644/777 permission. We are using UnityPlayerNativeActivity to send some instructions and get some variable values from UnityPlayer view. Also we have tried to load these library in code but even that does not work and these libraries are not loading.

We added this code in UnityPlayerNativeActivity System.load("/system/lib/libmain.so"); // Possible preload location System.load("/system/lib/libmono.so"); System.load("/system/lib/libunity.so");

App still crashes.

Is it even possible to make a unity app as system app?

Thanks.