Potty Training Dogs in Apartments

I usually take the dog for a walk and use the "encourage to do business" interaction or just Ieash them and do the same thing. I also tried sending a sim outside of the apartment building to see if they could call the dog down, and they could. So it seems that dogs can use the elevators the same as human sims. I think the family's cat did as well once, too, so I'm not sure why the "ask to go potty" interaction doesn't work when the dog is in the apartment.

I've also encountered an issue where I can't seem to actually potty train the dog. I take her out at least twice a day and have been for weeks in-game, but it still hasn't told me she's officially learned to do her business outside like it has with other dogs I've played. Unless this is a glitch, they don't seem to have thought through the whole housebreaking dogs in apartments situation.