[Solved]Body locks up when appling a constant impulse to it?

Anyone know why my body is locking up when I apply a constant (Key activated , makes no difference if there are intervals, it still locks ) force to it?

I'm using the impulse function to apply the force and it works perfectly at first but after moving for a certain amount, either colliding or flying through the air (Depending on the velocity of the force) it just instantly locks up.

I've deactivated auto-freeze, even tried continous collisions.

The collider is a convex hull of a static mesh.

Anyone experienced this or have any suggestions to how I could fix it?

Fixed it, the world size was too small, it was just hitting the edge.