I had tried various things to get my fitbit to agree that I was going upstairs. The only time it thought I was going upstairs was when I walked uphill dragging a water hose.
I read about it and it has an altimeter in it and you have to actually go up, not one step up and one step down because up and then down isn't changing altitudes. That was interesting. I'd gotten "floors" by accident, but I couldn't get them on purpose. So if I could find a flight of stairs, going up and down it would only count once. I guess I might locate a skyscraper and climb several flights. Not.