It seems the call recording feature of LG G4 T-Mobile LG-H811 is disabled by LGE (reported by an user).
Fortunately Boldbeast Recorder can bypass the limit.
No root needed, just install and go, Boldbeast Recorder records calls perfectly in two directions.
Please use these settings in the app to record calls:
- Record Mode: 5
- Record Format: WAV
- Tune Audio Route: Group3