CAREER MODE FITNESS BUG

This bug is ruining career mode.

This has happened to 3 of my players now, I'm playing an Arsenal career mode save and within this save 3 of my players have died. Stuck on 30 or less fitness rating no matter what training plan they're on. Timber has been on all out fitness for 6 months and he's yet to reach over 40 fitness without playing a single minute. Saka and Trossard are both the same. It's an absolute joke and is destroying the fun of the game as I can't use these players because they're unusable on 10 fitness. 
please fix this