Same problem
I am running Logic Pro x 10.4 with MacOS Mojave and I'm having the same problem.
Even more, every time I open the session, it just erases new files. This is a very worrisome situation.
At the beginning I also thought it was the external disk with which I was working. Then I started working in the computer, and only using the external for storage, but it kept doing it.
It looks like the photo attached, all the flat parts they had recordings. The face of evil
MacBook Air (2018 or later)