I don't know why I started having this problem. I tried saving some animations but nothing happened when I clicked the "save" button, no error message, nothing, the only saves on the list were some old ones.
I deleted all of the old ones and tried to save again, but this time it kind of worked, but not really. That new animation was saved, but with the name of an older one on the list, and when I tried saving again (not overwriting) I couldn't.
I had to delete that new animation from the list, so I deleted that one and saved again, but it just did the same. It creates a new save with the name of an old animation (and with the new animation).

I tried deleting that save from the data folder, but now I can't save even if the list is empty.
Is there anything I can do? I tried unistalling and reinstalling this addon, but nothing happened.