The system that add's flights to accounts is pretty basic, it checks your original flight first and can see noshow so does not add it. The system won't automatically check any other flights to see if you were on them and so does not add any. That's a very basic explanation, it gets a little more complicated but without prior knowledge of the program that takes care of EC profiles there wouldnt be a lot of point in explaining it. Hope that sort of explains it, I know this is pretty vague! Any other question i'll do my best to try and explain it!