(Phal) yellowing leaves and flower drop

Your plant looks like it's potted in sphag. If so, you need to repot it into orchid bark now. Sphag will keep the roots too wet. They need air around them. You should check the roots carefully for rot. Cut away any dying, dead or damaged roots(usually black), healthy roots should be white and fleshy,treat with a fungicide and repot in orchid bark in a clay pot with good drainage. Note that any blooms you have will most likely die due to the repotting experience, but at least you'll save the plant.

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It always rains after a dry spell !: