Failed to re-package resources (Android build)

Everytime I try to build my Android APK I get this error:

Error building Player: CommandInvokationFailure: Failed to re-package resources. See the Console for details. D:\android-sdk_r22.0.5-windows\android-sdk-windows\build-tools\21.1.2\aapt.exe package --auto-add-overlay -v -f -m -J gen -M AndroidManifest.xml -S "res" -I "D:/android-sdk_r22.0.5-windows/android-sdk-windows/platforms/android-21\android.jar" -F bin/resources.ap_ --extra-packages com.facebook.android -S

I already tried to use another SDK version (someone said that it won't work in 21.01)

I googled and searche in Unity Answers, but I can't find something to fix it.

Can you help me? Thanks in advance...