So after wasting SO MUCH time, I finally figured out what was the issue. The error occurred after I modified my project to be used as a library instead of an application. The problem stems from the fact that library modules do not define applicationId like application modules. The applicationId is specific to app modules, and library modules rely on the package name instead. Just remove the following fields from the defaultConfig block like so before after just remove these fields as they are not defined in the library modules.