No issues on mine when I had it, so maybe you have a hardware issue (that should have been addressed waaaay before if it's 'always been terrible', but that's besides the point now). Have you tried safe mode and/or the hardware check menu to see if everything is working on the basics? What about trying with someone else's fingerprints (to rule out that any callouses or scars aren't the issue)? What about the environment? Is it too dry where you live? If so, try (and I know, this sounds gross... But it works!) licking your finger before placing it on the sensor. Are you sure you're hitting the right area of the sensor?