As picture 5 shows below, it illustrates how to unlock the keyboard cable-lock, and move it 1-2mm cautiously.
Attention:
lift up the cable-lock on both ends by not more than 1mm.
Over lifting would break the clips that function to position the cable in place.

As picture 6 shows below, now it’s the time for the keyboard to get off from laptop, and then pull the connection cable out of it. And when install the keyboard, follow the steps above just by the opposite sequence.