I went to check on my plants this morning and saw this on top of my new Monsteras soil … I got her about two weeks ago & they repotted/fertilized her. Ive been spraying her as well as my other plants with ‘Garden Safe Houseplant & Garden Insect Killer’ as I saw a few gnats appear. I also purchased some ‘Bonide Systemic Houseplant Insect Control Granules’ to help combat them as well. Ive used the Granules once & the spray a few times & my plants look fine , yet this has occured. Can you all help me identify what could be causing this?