I use this for my camera system. It allows you to set the mouse delta sensitivity, which, if linked to your camera, fixes the camera sensitivity issue. My default is about 0.5 - 0.75 but it will vary based on the mouse. If it is a gaming mouse, the sensitivity can be adjusted on the mouse itself so you’ll have to add a sensitivity option in game.
I’ve heard it is frowned upon to use this alone as your sensitivity handler but it’s much easier and it doesn’t take as much math.
Edit: Saw you found the solution above. If you experience future issues, this should take care of all sensitivity issues.