Wilting/droopy leaves of your rubber tree is a sure sign that the plant needs a drink of water. Soak the plant in a bowl of tepid water for about an hour or so to allow the rootball to become thoroughly saturated; then let the plant drain completely. With it's broad leaves, the plant will need lots of water. Let the top 3 inches of soil becomes dry between watering.
Amor est vitae essentia. Love is the essence of life.
Wilted leaves, moldy soil ... doesnt sound good! You could throw away all the soil (but, obviously, don't put it on your compost heap) and carefully clean and prune the roots and re-pot in sterile soil. But I wonder if its worth the risk of possibly infecting all your other plants? Send it to Room 101!
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