One of the guys in my club found this. When you level up a players attributes to level 14 it goes to level 4 instead. If you go up to level 15 it fixes itself. And its accurate, his level 14 guys gets significantly worse when at level 14.
This issue has been posted here before, but apparently has not yet been remedied. I would recommend that anyone experiencing the issue submit a message to customer support, as this is an app-wide issue and needs to be fixed.
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