error in ScanActivity.java

[davideloddeDev]

Hi, my name's Davide. I'm having some difficulty in testing the package provided through this support. In the ScanActivity.java I get this error:

E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.nuboo.testscandocument, PID: 22829
java.lang.UnsatisfiedLinkError: dalvik.system.PathClassLoader[DexPathList[[zip file "/data/app/com.nuboo.testscandocument-gT9Z9Ekl_ifd-oxhmPAqcA==/base.apk"],nativeLibraryDirectories=[/data/app/com.nuboo.testscandocument-gT9Z9Ekl_ifd-oxhmPAqcA==/lib/arm64, /system/lib64, /system/product/lib64]]] couldn't find "libopencv_java3.so"
at java.lang.Runtime.loadLibrary0(Runtime.java:1067)
at java.lang.Runtime.loadLibrary0(Runtime.java:1007)
at java.lang.System.loadLibrary(System.java:1667)
at com.scanlibrary.ScanActivity.(ScanActivity.java:125)
at java.lang.Class.newInstance(Native Method)
at android.app.AppComponentFactory.instantiateActivity(AppComponentFactory.java:95)
at androidx.core.app.CoreComponentFactory.instantiateActivity(CoreComponentFactory.java:45)
at android.app.Instrumentation.newActivity(Instrumentation.java:1243)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3182)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3409)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)

Point by point the line reported by Android studio is this:
System.loadLibrary("opencv_java3");

would you have an idea on how to solve?