This problem is quite old, but in recent months and weeks it appears more often and is really annoying. I'm watching my game from the start, don't leave, don't have any connection issues, make a substitution... Usually it works fine, but from time to time, and now it's more often than in the past, the substitution happens with a big delay or doesn't happen at all!

Delay of 10 or 15 minutes is nothing special. Today I had a cup game, was losing 0:1 at half and needed to score a goal at least, made an offensive substitution in some 60th minute - but nothing happened till the end of the game! Now I'm out of the cup and had no chance to do anything with it. I guess other tactical changes I made didn't happen too... Few days ago I did a substitution in 35th minute, because my CB was sent off - nothing happened till the end of the game and I lost it too of course...

(no, of course I didn't forget to save the changes)