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Also it’s really hard to diagnose anything in blurple. Try turning the lights off and your flash on, also include a pic of the top of the plant. Just a cursory glance looks as if you are suffering from some kind of root rot or even damping off which is a condition caused by watering too frequently / not allowing the soil to dry out properly between watering sessions. I’m pretty confident those branches will die given how bad the damage is, however I could be wrong. Damping off mostly hits seedlings and I’ve never seen it on a large plant but anything is possible. Same goes for the smaller plant beside it - way too much water.
