I can only access one chunk of the Nether.

I have been having issues with the nether. Whenever I go into the portal, I spawn in an area with a single chunk. Nothing else. just the one chunk. From what I can tell I am in a soul sand valley, but I don't think that has anything to do with it. Whenever I break a block with the proper tool, it drops nothing. Whenever I drop an item, it disappears. Whenever I try to return to the overworld, I remain in the portal animation loop. Whenever I try to build outside of the chunk, I am disallowed. Whenever I jump into the void, I can't die. And whenever I quit to the title, the game never fully saves and I cannot close the window.

The saves retain some information, though. The first time this issue occurred, I had caught a lily pad and name tag, crafted and placed an anvil, named a zombie villager, and crafted a tripwire hook and crossbow before lighting the portal and entering the nether. When I closed the game and came back, I had one tripwire hook but no crossbow, the zombie was unnamed but I had no name tag, and I had an anvil placed. The portal remained unlit.

After I altered my inventory, went into the portal a second time and reopened the game, the portal had been lit but my inventory reverted to its original state. I could provide a video, if it serves as a better descriptor for this issue.