I hear a grinding sound and then an error beep when trying to operate the lock.

Is you hear any grinding sounds when trying to operate the lock there is pressure on the clutch mechanism, which can be from installation misalignments. Remove the lock from the door and ensure that the holes drilled are correct as per the template and in line as per the template. Ensure that when you are reinstalling the lock, that the spindles are fitted into the latch hole.