hello, I went to install Catalina and it crashed during the install. Apple support offers no assistance, so I did a reinstall of Mojave from a time machine backup. The computer is nearly unusable (speed wise) and there is a new disk "Macintosh HD - Data" that has appeared that seems like a duplicate of my original HD but taking up 2x the space. I have a 2TB drive, and the original drive now shows 700GB and the new drive has 1.2TB. Any assistance would be appreciated since the Catalina feedback assistant as not responded.