If you have a couple of dumbbells/anything heavy. The heavier the better, but make sure they are equal weight. Pick them up on both sides. Pinch your shoulder blade. Tuck in your glutes. And do the farmer's walk for a few rounds. No need to do it for a long time. Just a few minutes.

It fixes postures. Long term it's better than quick fixes like applying some medication or going for a massage.