Left Shift key launches Mission Control

So I finally got this resolved, had to have an Apple technician walk me through it. Turns out that even tho Mission Control did not state LEFT SHIFT would launch it, LEFT SHIFT was launching Mission Control. So all we did was go to settings, Desktop & Dock > Keyboard and mouse shortcuts > and in mine, Mission Control was set to CTRL UP ARROW. So we set Mission Control to LEFT SHIFT, then back to CTRL UP ARROW and that solved it! Hope this helps you too!!

Okay so in System Settings > Dock and Desktop > Shortcut Buttons, I see the below which states Mission Control setting conflicts with another setting in Keyboard Settings. When I click on Keyboard Settings, both Mission Control settings are set to the same thing (control + up arrow), none of which is the 'left shift' key.

I also tried restarting my computer and now the left shift key is displaying all open windows from the current application, so if in Safari, I press the left shift key, it arrays all my Safari windows. If I press the left shift key down quickly multiple times and keep it pressed, it switches between open windows, comes back to the original, and then I'm able to use it as a normal shift key (to capitalize a letter for example)...this is so weird and terribly frustrating. It's almost as if the shift key has dual function now, but the normal use of it, to capitalize a letter when typing, is the secondary function of the key and only accessible once I press down on it twice quickly and hold it down. I'm not sure how this happened...

No I’ve not figured it out yet…so frustrating. Only work around I’ve found so far is to increase the window I’m working in to full screen and then that somehow lets my SHIFT button act like a normal SHIFT button. Otherwise LEFT SHIFT is still trying to array all open windows from whatever application I’m in.