Plutonium

Hey guys bear with me because I'm still relatively to this community and whatnot so I'm not super good with the technical stuff, but basically my issue is that I am an avid zombies player and sometimes my stats for a session just don't save at all when I quit the application seemingly at random. Is this a known issue or is there something I can do to fix this? I hate playing for a couple hours only for it to completely disappear for seemingly no reason :(.