After a long search I haven't found any solution. I have the same problem myself, since the Lock key is right above the backspace key I often use.

The only trick that helped me is to switch the ESC button I don't use often and backspace button in the key mapping in Settings / Device / Keyboard / Customize keyboard keys. That way my backspace is on the opposite side of the keyboard, far away from the Lock key (not customizable). But I have to adapt to the new backspace position after years of use.