skill gem bug causing malfunction

my usual Cold Snap skill gem suddenly became unusable, on skill panel it no longer display DPS or DMG while other skills works fine. the detail skill panel showing "this information is currently unavailable", and the bottom right skil slots cannot equip Cold Snap anymore.

Saw quite some similar cases by searching "skill gem" in this forum but no solid fix, most players just remake a new gem and give up on the old gem....

Any advice please?