We checked the Android 5.1 ROM of LG G4 Verizon VS986, the call recording feature is disabled by LGE. You must have found all other recorders can only record your voice, the caller's voice can't be recorded.
Fortunately Boldbeast Recorder can bypass the limit.
No root needed, just install and go, Boldbeast Recorder records calls perfectly in two directions. This is the only solution in the world that works well without root for your VS986.
Please use these settings in the app to record calls:
- Record Mode: 1 or 5
- Record Format: WAV
- Tune Audio Route: Group3