One of my rental houses is starting to show signs of possible mold coming out of the air vents. There are some black spots showing up on the area around the vents.

I have a cleaning crew coming next week to take a look at the ventilation system but is there something else I should be doing in the mean time?

Has anyone else dealt with this issue before?

Thanks

it's probably mold growing on the ceiling/vent, not "mold coming out of the vent".
happens when it's too humid

Follow the mold removal steps given below-
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Conduct a mold test to identify the type of mold.

Identify the causes of mold in your home.

If mold has spread around the insulation, replace the insulation material immediately.

Clean the air vents properly.

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