That looks like PokerTracker 4 is only importing observed hands from PokerStars and not the hands you actually play so please make sure everything is
setup correctly in PokerStars. Is your PokerStars client set to save your hand history files? You can check that in:
PokerStars Client -> Settings -> Playing History -> Hand History -> [x] Save My Hand History
If it's set to save the hands then is PokerStars actually creating the hand history files on your computer while you are playing? Go to the folder set in PokerStars and there should be a folder with your player name and inside that folder would be the hand history files. I've seen on occasion hand histories not save to the default location (C:\Users\{Windows Login}\AppData\Local\{PokerStars Skin Name}\HandHistory) so if that's the case try creating and setting a custom hand history folder (e.g. C:\StarsHH) instead in both PokerStars and PokerTracker 4.