I\'ve just received this message from Google Play but I\'m not collecting the Advertising ID.
Reason for warning: Violation of Usage of Android Advert
According to the Firebase docs you can disable advertising id collection by setting:
in your AndroidManifest.xml under the tag.
EDIT: It seems like people are having mixed success with this approach. Try adding
configurations { all*.exclude group: 'com.google.firebase', module: 'firebase-core' all*.exclude group: 'com.google.firebase', module: 'firebase-iid' } to the Gradle app dependencies area as per comment below.