Random particle orientation issue

So I have developed an explosion using the particle system in UE4. The explosion has two smaller trails coming from it (see pic). I want to randomise the particle system’s rotation each time I spawn it so that the trails are not always the same direction.

I have used the world offset (Seed) for the particle trail motion (See pic) even if I just drag this particle into my scene and try to apply a rotation it still sticks to its original rotation angles.