It's not a known issue as far as I know and you can re-open your existing support ticket on this topic by replying to it again including log files and hand histories:
Guide: How to Create & Submit a PokerTracker4.log FileCompress all of the files there (not the Archive folder, just the files) and attach that to your reply along with the generated hand history files for the session and the relevant sample of downloaded hands. If you haven't stopped auto import yet the grabbed hands will be in HandHistory\Ignition but after that they'll be moved to your \PokerTracker 4\Processed folder which you can access via the 'File -> Open User Data Folder' option.