I cannot turn on/off the camera with RM-LVR3.

When you operate the power button of RM-LVR3 continuously, the power of the camera which is paired with RM-LVR3 may not operate with RM-LVR3 simultaneously. Wait about 5 seconds or so before trying again.

The power of the camera may not operate with RM-LVR3 simultaneously depending on your surroundings or if the camera is distant from RM-LVR3. Move closer to the camera and operate the power button.