Gradle ' ' project refresh failed:Could not find property 'VERSION_NAME' on project ':FreemiumLibrary'.

[donglp1810]

I try add this library to android studio. with archive like: I acquired this occurrence like: And bug: gradle project sync failed, this like: You can help me fix this bug. And guide how add this library to to android studio I following this guide: https://github.com/MagicMicky/FreemiumLibrary/wiki/Import-the-library-in-Android-Studio