Yep I’m having the same issue with my new story. It initially showed up as under 100 when I switched its genre, but now it’s stuck at 101 and won’t go lower. I have other stories in this genre that have been reviewed and are showing as trending higher but they’ve definitely had less reads in the same time span. Overall ranking for the new one is also better.
It looks like someone above had the same question but was never answered.