I have reported about that in the past in one of the previous periods I played the game. Lately I noticed the problem occurring again. At least twice it has occurred this week. The substituted player was still shown to be playing on the pitch via the highlights, that is the round thing with his number and his name labelled to it still moving on the pitch as if the player was still playing. I assure you that I substituted the player, and substitution also occurred, that is, it was shown by the comments (X comes off for Y) and also on the highlights page (name, green arrow | name, red arrow. Also, those substitutions were done early enough; the latest one was done at the 63 min mark.