Do you mean PokerKing which is on the Winning Poker Network (WPN) or PokerKing (Asia) which requires a converter?
What update are you referring to? The recent update to PokerTracker 4 or an update to PokerKing? Are your hand histories still being created and imported?
If you are on PokerKing (WPN) and it recently updated then with PokerTracker 4 not running please run the poker site installer again and that should get things working. Sometimes after an update WPN Network poker sites will remove the hand history folder and fail to write your hand histories. Reinstalling will fix that.
If it still doesn't work after that please check that hand history files are being saved as you play and that you have the correct hand history folder configured in PokerTracker 4:
WPN Configuration Guide