The picture of your root system & reservoir looks like your air stone isnt producing enough bubbles. Make sure your pump & air stone are operational.
I just checked the Stone this morning. It’s working. The roots are wrapping around it though.
I would remove the whole plant, tray, roots & all & gently as possible. & really check I had this problem where my pump was intermittent. The air stone was producing bubbles but very minimally & my plant was digressing rapidly. Once I replaced the pump with a small aquarium pump till support got me a new pump, it changed her within 24 hours she wasnt weeping anymore & started to pray.
Lift the plant & roots as high as possible & send another picture of your reservoir it should be bubbling real good.
& you could be very well right that your pump & air stone are working fine. Its always good to cross all Ts & dot all i’s.
What amendments are you currently adding to your recipe?