Many of us have noticed that A6000 series cameras are very sensitive for third-party batteries, giving the message "Incompatible battery – use a compatible battery".
I have had incompatible batteries, but changing to an original one does not help. The message just does not disappear and the camera cannot be used.
During the guarantee time the A6500 was repaired twice for this and I have not used 3rt party batteries ever since. However, now the camera is giving the message again. I once heard that a Sony owner had succeeded to fix it himself – if I remember right he simply put the camera on and off very many times.
Any other magic to try?