I am having a problem with projectiles in a platformer

I am making a 3d side scroller platformer kind of thing and i am using projectiles like a bullet. The character at the moment when turning from left to right or vice versa does a rotation but when i shoot during the rotation the projectiles go off the plane.

Basically what i am asking is how to keep the projectiles on 1 axis

If you look in the details of the movement component on your projectiles (bullets, etc), there should be a setting for movement constraints. Just have to figure out which plane/planes you want to restrict movement to and plug in the proper values. Attached is a shot of the box in the movement component you’re looking for.