Does anyone know how to fix this lighting problem on 1.16.5?

[Avante]

My lighting is on maximum, and I've done everything I could, even googling it. But I've found nothing to fix this problem. In the image, theres the weird blackness under slabs and stairs, like theres no lighting there. I want to find a way to get rid of that, as its never happened before.

[shizuka]

That looks like Hypixel to me, and if so I am not surprised. In order to cater to players that stay on 1.8 to abuse the reach/rapidhit bugs plaguing PVP, Hypixel still runs on version 1.7 which causes a lot of weird lighting glitches for players that actually update and play on the newest versions since I think they changed the lighting engine at one point.

If this is on a single player world, it is likely client side and just a visual glitch that should be solved by exiting and re-entering the world