Joonie
Seedling
I’ll definitely spray the soil then as well as the littlesI can't tell from the pictures...but try and get a positive ID on the critters. Some critters can live in the soil even if they prefer living on/under the foliage. Treating just the foliage if it's that type isn't good enough.
Also, I at least see a cacti and another pot close by in your pictures. You need to treat them too. Depending on the critter, the cacti may be too thick skinned to be lunch...but the needles could harbor nests.
i did monthly preventative treatments, i think it happened when I moved inDo you know what they were when you treated it before? Did you treat all the neighboring plants at that time as well?
It could be a re-infestation from a nearby neighbor if everything wasn't treated with a strict regimen