Repeating fungus gnats as the answer. I use a few strategies to manage them:

• yellow “sticky strips” (can be purchased at garden stores and Amazon) that you stick into the pot. They’re ugly, but the flies love them.
• dish soap bath for plants that can handle it (the blue Dawn extra strong soap is best).
• bottom watering, or letting the top of the soil dry out between waterings

Humid environments require lighter watering. You might want to get a soil moisture detector so you can see how moist your soil really is and determine if you need to water.