Glad to assist you with connecting a fenix 2 to Garmin Connect Mobile.
Thank you for being a Garmin customer. Ensure the location services are turned on for the Android devices.
Location Services Required for Garmin Connect Mobile App in Android 6.0
With the release of Android 6.0 (Marshmallow), Google has changed the permissions required for Bluetooth syncing as explained in their Android 6.0 Changes document. You now must enable Location on your mobile phone in two places before you can successfully pair and sync your Garmin device with Garmin Connect Mobile (GCM).
First, please check compatibility between your phone and device by reviewing thecompatibility list.
Once you've verified compatibility, access your mobile phone's Settings app and enable Location services.
Now you must enable Location permissions specifically for GCM. To do this, access your mobile phone's settings, touch Apps > Connect > Permissions > enable Location. Images below show this path on a Nexus 6 but should apply to most Android phones running official Android 6.0.
As a reminder, this should only be required on Android 6 (Marshmallow). If these steps don't resolve any syncing trouble you're having, or if you're using a different version of the Android OS, please contact product support for assistance.
결론은 "핸드폰 문제일테니 알아서 해라." -_-+
검색을 해보면 과거에 지들 서버 문제였던 적도 있었으나, 서버 문제라는 말은 없고 안드로이드 권한 문제라고 하고 있는데....
