Chunks are not loading only in my World

I ran Minecraft version 1.16.3 and at the begginnig started with version 1.16.2. One day all of the sudden game starts to not render chunk but i could see the block hitboxes. Then chunks took so long(like 30 seconds) to render. Then right now i'm stuck in a chunk. I tried to use optimize world option and still didn't worked. Here are some screenshots :