Latitude E6430 keyboard failure.

Hello everyone!

two days ago, the keyboard of my laptop stopped functioning correctly, in the beginning, any key corresponded to their functions, so I restored the system to a previously configured point, and after that, the major part of the problems was solved, but some keys continued to have.

In normal mode the keys "Esc", "|", "1" and "Tab" don't have any utility, |the key "q" also has the "media play/pause" functionality, the key "a" some time write "ak" or "ka", the key "F11" also has the "1" functionality and the key "Delete" also has the "|" functionality.

When the caps block is active, the key "Esc" active the "F4", "F5", "F6", "Alt", "G", "H" and "up arrow" keys, the key "|" active the "Ctrl", "F1", "F2", "5", "6", "F8", "F9", "'", "¿", "Insert", "Home" and "Delete" keys, the key "1" active the "Win", "2", "3", "4", "7", "8", "9", "0", "F10", "F11" y "F12" keys, the key  "Tab" active the "F3", "T", "Y", "F7", "Back Space", "'", "¿", "shift" and "caps block" keys, the key "rigth arrow" active the "B", "N", "Space", "Alt Gr", "Left arrow" and "Down arow", the key "F12" active the same keys that the key "1" aknd the key "Insert" active the same keys that the key "|"

I have tried to reinstall the keyboard drive, also I have reinstalled a clean version of Windows 10 without solving the problem, but I don't think that it's Hardware because I have cleaned the keyboard and it looks in a perfect state and because when I have restored the system and when I have to reinstall the OS, the keys activated by each key mentioned previously, has changed, for example sometimes after a restoration o reinstallation, the key "tab" active the "caps block" and some time don't active it.

Could someone explain to me what the error is here and how I can solve it?