black mold spots on my backs of my phal leaves

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Fungal and bacterial infections are very uncommon inside homes because the humidity is rarely high enough. Even in my sunroom, with relative humidity often 60% or higher, I have never had any fungal issues. I have never used any fungicides, nor cinnamon. I had Erwinia once on Phals. when I had to close it tightly for two weeks during the hottest part of the year when I had surgery and couldn't care for my plants. The relative humidity was probably above 90% with temperatures always above 85 F / 30C.

You likely have fungus growing on something smeared on the leaves, not on the plant itself. This kind of fungus is rarely invasive. Spots on leaves in homes or lower humidity outside areas are almost always problems with culture rather than infections.