Chunk completely gone

Traveling along the river on a boat and I see the square dread that is, of a missing chunk. I was hoping it was just a visual glitch. I exited and made a copy of the world to investigate in. I fell to the void and died. Going out of render and back did not fix it. Saving and rentering did nothing. Clearing cache did not help. Restarting my tablet did not help. This has never happened before. I didn't play with mods or editing stuff. Pure vanilla survival. I have a picture of the missing chunk in a creative copy of the effected world. Nothing happened before this to indicate something was suspicious.

 

Edit: For clarification, the diet blocks inside the chunk on the right, was me investigating. It goes straight down the void. It is not a visual glitch unfortunately. It's the real deal.