If you haven’t checked your set screws - it was the major pain point I had as a newbie and I was seeing the exact problem you were showing in the first post.
It was deceiving because I checked multiple times and they seemed tight, but it doesn’t take much slippage to translate to a big problem in your cut. Here’s my original post describing the problem:
Switching to better set screws with a dot of low-strength thread lock is a simple and inexpensive solution to try.