Random Sims Enter My House, Cannot Get Them To Leave. June, 2020

Ok, first to clear all of the usual questions up when this problem arises:

1. I don't run ANY mods in my game

2. I have checked the lot type and it is set to residential

3. I have the doors locked accordingly

I built a house for a Sim of myself in Sulani, and this is now the second time a random Sim that my Sim doesn't even know has entered my home - and there's no interaction to get them to leave after you try the first time and they just continue to sit there.

I've never seen this sim, or interacted with them. They just showed up, sat on my couch, and started watching TV. I've tried resetting that sim, I've tried being mean to them...she just lingers.