on character screen when u go to change your weapons gear, at the top right corner of screen there will be a small settings symbol click on that then scroll to settings for your keyboard and look at list and change your settings to how you want to play. make sure save. problem should be fixed. if not then double check makes sure you didn't accidentally put same key for different things because then it switches to last one so it's not what you thought it was... {if that makes sense}