You do not mention how you set your blade depth, so start there. Sounds like too much blade exposed.
To start with, you should set your blade depth correctly, by taking the blade holder out of the machine, and firmly cut across a piece of scrap vinyl, you will be cutting. You should only be cutting the vinyl and barely a mark on wax paper backing, Adjust blade to get there, Then put the blade holder back in machine, and use the force of the machine to get there, same results, only cutting the vinyl and barely a mark in wax paper backing. You should just barely see and feel the blade tip out of the blade holder. You only cut with the very tip of the blade.
You were advised on your first post that you have too much blade exposed, you may have adjusted it some, as you stated it was shredding the vinyl. But still sounds like too much blade exposed. This is the correct way to set it. We don't know what you saw online, there are many wrong ways out there to set blade depth.