Toshiba Satellite touchpad keeps turning ON while typing

My Toshiba Satellite laptop touchpad keeps turning back on in the middle of my typing. I'm not pressing the Fn+F5 keys to do it, so I can't figure out what's causing it. I'm not even using the F5 keys or Fn key at all when it happens. The touchpad doesn't have the left-hand corner option where you can double tap to enable it, the only way to enable or disable it is through the Fn key or mouse hardware settings options, and I've disabled it both ways (many times), but it still keeps coming back on and messing up what I'm working on. I'm a graduate student writing lots of papers, and this happens many times a day and is messing up my papers. Help!! Is there maybe an unknown keyboard shortcut I might be typing, or a way to permanently disable it? I never use it.
Thank you!