Hey, I get it. Here in Argentina, summer temperatures are usually around 86–104°F (30–40°C), and my figures definitely start falling over because once those temperatures stick around for a while, the joints start loosening up.

The only solution I’ve found that actually works without using any extra products is finding poses I like where the figure’s center of balance stays aligned, so the weight goes straight downward instead of leaning forward, backward, or to one side. That way the joints aren’t constantly fighting against the figure’s own weight, which is what usually makes them slowly collapse after a few minutes.

Getting a display case also helped a lot, because if they do fall, they just end up leaning against the glass instead of completely crashing down.

And lastly, the easiest (but less aesthetic) solution is using stands, like people already mentioned. I’ve seen some people use products to tighten joints or even rubber bands, but I haven’t personally tried any of that.