MacBook Pro 2015 NVRAM Errors

hi,

after some idle minutes or when I log off my mac the mac has (maybe) a nvram error. The keyboard doesn't work anymore.

I Need to connect USB board and a mouse to reboot and reset nvram. Then it works for some hours. Even after reinstalling sierra the failure is still present. I also used the apple support via phone and the hint was to use an different user and see if the failure still there. But I need my mail connections and I already reinstalled sierra so the user isnt the same anymore.

does anyone know this failure? I do also have some movie of the failure..