Another thing to think about could be your setup and I didn’t see anyone ask when skimming the other replies. Are you on a smart trainer or virtual power? I train with a fluid turbo trainer at home and a bike with a power meter when I’m at work, the virtual power really wanders from reality (it certainly feels like that) in the VO2 max arena.
I really used to struggle with VO2 max until I started training with a power meter at work and now I have to have two different thresholds to have the right baseline for a workout but I try and manage it so that on a ride at home I do SS to threshold where I feel it is more accurate. I do VO2 max etc at work.
Also maybe reset to the first introduction Chad gives you, start in 30 seconds blocks and build it up again.