FPS Run Animation Problem with Rotation

Hey Guys, Recently I started making an FPS Game. When I reached the animation creation I realized that when I tried to make the Run Animation I changed the rotation of the weapon -45 degrees (everythings fine so far). When the run animation was being interupted by the walk animation (for example when you Get the button up) my weapon does not change its rotation to the default of the walk animation (0 degrees) it just stays the same -45 degrees.. how can i fix that?