Same here, post from another thread:
Daniel
Training is broken here too and it seems it's so for several managers in my league (car repair and engine replace was mentioned as broken as well).
One of my drivers, similar to Alex, with 5 yellow stars unlike yesterday trained with 3% steps today and after he leveled and got 5 red stars the training doesn't work anymore for both drivers. Pressing the train button disables it for a few seconds like normal but without any visible results.