Sourdough dough collapsed, not rising again... Need help! A few days back I started a bread following a Youtube recipe, it had 400gms of flour and 350 gms of water. I had never made such high hydration bread before. I did 1 hour of autolyse followed by 4 round of 5 min kneading by hand. Still it was rising slowly, so I left it on the counter overnight (22-24°C).

Next morning it had doubled. But when I started lightly it folding for final proofing, it just collapsed into a sticky mass. I waited for 2-3 hours and when it didn't rise I added another 150 gms of flour hoping that it would rise again. But I'm waiting for almost 30 hours but there is no gluten development or rise!! Even the no knead sourdough dough rises much faster!

Could anyone explain what's going on and if there'a chance to revive it?

PS: I have been making 2-3 sourdough bread every week since the lock down due to COVID19 started. Some of them were no-knead bread, some were kneaded bread and most of them turned out pretty good. I just mentioned it to let you know that, although I'm an amateur, I'm not a complete novice for sourdough bread and my starter is good!
This sounds very much like overproofed bread. You should have baked it much sooner, or retarded it in the fridge, not left it on the counter. 

You cannot "rescue" overproofed bread in the sense that the loaf will never have good texture. If you really want to save the ingredients, you can reuse them as a preferment in a new bread. But it is not necessarily worth it, since the overproofing process creates very sharp off-flavors.