The emulator must enable the Google APIs for Google Play services. To resolve this issue, the mobile developer must create an emulator that uses Google APIs as the target OS. Also, when the mobile developer sets up the emulator, make sure that the Android Virtual Device (AVD) uses a target with Google APIs enabled.
This issue can occur when you test the mobile app that uses an Android emulator. You can connect to Acoustic Campaign and verify that a mobile contact record is created. However, when you attempt to trigger a push notification, the message is not received on the emulator.