My guess is that you're fading out early because you don't have enough speed on the putt or the apex of your arc is too high. Hard to say without seeing video, but I see people make these mistakes with the pitch putt.
Bfowler gave a lot of good advice and I wanted to expand on the "spring your fingers" part. This is one of those "hidden" techniques that often gets glossed over when you watch youtube videos of the pros doing pitch putting clinics, but it's actually really important. If you're using a standard fan grip for putting, then the your fingers are the last thing to touch the disc. They are going to transfer, to the disc, all of the power you've built up with the rest of your putting motion. So if your grip is too soft at the moment of release, you're not going to successfully transfer that energy and your putt will either be too slow, wobbly or lacking spin.
You'll want to keep a relaxed, but firm hold on the putter all the way through the putting motion until right before the release. Then squeeze down hard between your thumb and your middle finger, ring finger and pinkie. This ejects the disc with a lot of pace and also imparts quite a bit of spin. It's the reason people like Wysocki have these effortless looking pitch putts from 40+ feet out; they're not losing any energy, all of it is being transferred into the disc.
I would also recommend putting on a slight hyzer angle if you're not already. Putting with a flat or anhyzer angle will cause you to lose power.