Почему не билдится проект на Android?

Доброго времени суток, друзья. Пытаюсь сбилдить проект в Unity для платформы Android. Было всё норм, а сейчас начал билдить проект и вываливается ошибка

CommandInvokationFailure: Gradle build failed.
C:/Program Files/Java/jdk1.8.0_171\bin\java.exe -classpath "C:\Programs\Unity 3D\Editor\Data\PlaybackEngines\AndroidPlayer\Tools\gradle\lib\gradle-launcher-4.0.1.jar" org.gradle.launcher.GradleMain "-Dorg.gradle.jvmargs=-Xmx2048m" "assembleRelease"

stderr[

FAILURE: Build failed with an exception.

* What went wrong:
A problem occurred configuring root project 'gradleOut'.
> Failed to find Build Tools revision 28.0.0

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

BUILD FAILED in 22s
]
stdout[
Starting a Gradle Daemon, 1 incompatible and 2 stopped Daemons could not be reused, use --status for details
NDK is missing a "platforms" directory.
If you are using NDK, verify the ndk.dir is set to a valid NDK directory. It is currently set to C:\Users\dword\AppData\Local\Android\sdk\ndk-bundle.
If you are not using NDK, unset the NDK variable from ANDROID_NDK_HOME or local.properties to remove this warning.

File C:\Users\dword\.android\repositories.cfg could not be loaded.
]
exit code: 1
UnityEditor.Android.Command.WaitForProgramToRun (UnityEditor.Utils.Program p, UnityEditor.Android.WaitingForProcessToExit waitingForProcessToExit, System.String errorMsg)
UnityEditor.Android.Command.Run (System.Diagnostics.ProcessStartInfo psi, UnityEditor.Android.WaitingForProcessToExit waitingForProcessToExit, System.String errorMsg)
UnityEditor.Android.AndroidJavaTools.RunJava (System.String args, System.String workingdir, System.Action`1 progress, System.String error)
UnityEditor.Android.GradleWrapper.Run (System.String workingdir, System.String task, System.Action`1 progress)
Rethrow as GradleInvokationException: Gradle build failed
UnityEditor.Android.GradleWrapper.Run (System.String workingdir, System.String task, System.Action`1 progress)
UnityEditor.Android.PostProcessor.Tasks.BuildGradleProject.Execute (UnityEditor.Android.PostProcessor.PostProcessorContext context)
UnityEditor.Android.PostProcessor.PostProcessRunner.RunAllTasks (UnityEditor.Android.PostProcessor.PostProcessorContext context)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)

Никогда не было такого и не сталкивался с этим. Подскажите пожалуйста, как решить ?

Заранее спасибо огромное!