OmarLoggi

Youâre a genius. Iâve got the Better Vampires mod downloaded and it offers 2 choices to slow down your speed for attacking. Disabled that and it works perfectly

  Do you have any attack speed edits? If you have more than one (Disparity adds one if you use that, as do many other mods), it will definitely have problems. If you have one try disabling it. If that doesn't work, try this in the console command; player.setav weaponspeedmult 1 ^this is the default value. I've had it happen to me a few times and that usually fixes it.