CKAPP01 / display material to cost: costed material remainin

[vincedegre]

an extract on this T code has been done on my database.
There are only Two material remaining, one is previous cost maintened, and no current (because it has been obsoleted froùm plant )so that is normal (sales activity is still maintened in active)
but the second one is remaining instead it has a previous and current cost. (sales activity active and plant active.)
All the components in the Bom are rightly costed (green light) so Could some one explain me why the second part is remaining in CKAPP01 while the cost is maintened?
What should be the root cause
Thanks for your vision on this subject
Vincedegre