Most likely a combination of two things: a troll downvoting all questions and some issues with restoring reputation (recalculating after deleting the votes). I'll answer, once we have fixed this.

I just checked, and there seems to be nothing in the mod tools to look at voting patterns at all. It would be nice if each of us could see recent rep changes, like there was on SE. I asked for that at https://meta.codidact.com/questions/276332, but was largely ignored, or it got used to malign rep instead of addressing the question. I think my rep went down too, and I can't tell due to which posts either. That sucks.

This should be fixed now. Some rep was over-reported, and then there was an issue in some troll-mitigation changes that made things go haywire. We believe the rep numbers now showing are the true numbers.

Well, it's risen back a bit from 316 to 321 but it still hasn't returned to circa 352 so, I'd say that it isn't fixed. I agree with Olin, about mods getting the right tools to do the job. As a plain ordinary user, there isn't enough information that I can find that tells me where up-votes or down-votes came from either. Maybe I'm missing something here?

Related: https://meta.codidact.com/questions/276808

@Andy: You should be a mod here anyway (even though this has nothing to do with this particular question). You are one of the original core group that proposed this site. I don't know how to make it happen. Perhaps the admins don't realize you were one of the original core.

@Olin - not sure I was. I can't remember proposing a new site. Maybe it was something I said once? Hold fire on me being a mod.