Have you tried an indoor/outdoor bug spray? I don’t usually like to resort to that, but sometimes with bad infestations I take the plant outside (in the morning/shady spot) and spray it down with this:
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that's what i use! Hope it helps!
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this spray got rid of a lot of pests for me!
This is my lord and savior https://www.amazon.com/gp/product/B07D7HFDSZ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1