I can't test this just yet, as I am at work. But your keybinds are stored in:
C:\Users\<yourname>\My Documents\Arma 3\PV1%20Rivas.Arma3Profile
or
C:\Users\<yourname>\My Documents\Arma 3 - Other Profiles\PV1%20Rivas.Arma3Profile
Cut/Move this file to your desktop while Arma 3 is closed, and start up the Game. It may rebuild that file. If it does, it will completely reset your keybinds. If it doesn't, the next step would be to add a new Profile in the Arma 3 Main Menu Options.
I can do some more testing when I get home if you still need help. This is all I could find right now.