Unity crashes when erasing tiles on a tilemap and entering those empty tiles.

I've had this issue for a while now, however cannot figure out any fix for it. Though I've narrowed down how I replicate it.

Basically, the Tilemap for my game, works fine when I run it. It has worked fine and well for a long while now. If I am to erase a single tile on my tilemap (and by that I mean using the erase brush and removing a space in the scene itself) it will operate fine until I enter that space (or any other gameobject for that matter) and the entire engine crashes. Because of this, I have been using the same scene layout for several months. I can add and replace tiles with ease, however if I add a tile and then erase it then I am met with the same crashing issue.

I have tried disabling the tilemap once tiles have been removed. Even while not in the scene, it remembers where those spots were and crashes me when I go where they once were. I have turned off the entire grid, to the same effect and the same crashed engine.

I have no code attached to any of these tilemaps and no code that references any of these tilemaps either.

I have tried reaching out for help in some places, but it seems very unheard of. Though I am using an older version of Unity, 2018.3.6f1. And no, I can't update it, I wish I could, but that's out of the question. I really have no idea anymore... and I haven't seen anyone with an issue even closely related to this.