Changing attributes in FMSE18 doesnt work well

First off, ive noticed this before, for some months now.
When i change something, recent example:
Work Rate. it was 10 put it to 20.
over time, here it was 4 days, all the other attributes take a deep dive getting lowered by 2 or 3.
Am I doing something wrong or is this a bug?

like i said, this happend before with different save games.

kind regards
nick

If you don't adjust your current ability also, the rest of the stats will reduce to keep the current ability accurate I think.