What is that substance growing out of my ceiling I thought it was a mound of dust about a quarter inch big then I wiped it off and saw the paint was missing It grew back again after a few hours?

The substance you're seeing on your ceiling could be mold or mildew, which often appears in damp or humid environments. It can resemble dust but typically indicates moisture issues, such as leaks or high humidity. Since it grows back quickly after cleaning, it's important to address the underlying moisture problem and consider consulting a professional for proper removal and remediation. Letting it persist can lead to health issues and further damage to your property.