Wilting peace lily
The problem is most likely due to a water issue. Too little water can cause wilting, and too much water also can cause the same symptoms. Allow the half-inch or so of the potting medium to dry out between waterings, and never let the plants sit with water in the dish underneath the pot.
It looks like there is some build-up at the base of the pot in your first photo. Soluble salt build-up might be another problem that has led to the symptoms you see. If mineral salts build up to a high level in the soil, water is drawn out from the root tips, damaging the roots directly.
You can find more information about watering and soluble salt injury on the following page of our website. https://extension.umd.edu/hgic/topics/watering-and-soluble-salts-houseplants
You can try repotting your plants into fresh soil medium, but if they have been wilted for too long, they may not recover. Peace lilies like to be in medium indirect light and they should be kept away from cold drafts.
Peace lilies also are sensitive to dry air. You can set the pots on top of trays of moist pebbles to help improve humidity around the plants.