Stock only showing for main location

I’ve got 3 locations total. My process is to upload new products with the stock information as meta data (e.g. location 1: 3, location 2: 5, etc.), and then mass-edit the products to “turn on” the stock locations.

The problem I’m encountering today is that I can’t “turn on” my other locations; only the main location is showing for these products. I will update it with Quick Edit or go into the product itself in Edit, but the change isn’t sticking. On refresh, it still only shows stock for the main location. No matter how many times I try to save, the update won’t save.

I tried disabling my cache plugin, but that didn’t help. Nothing is showing in my error log. I’m all out of ideas.