Might be a bug, using paint brush on 6th landscape brush removes all textures from cell

Everything is identical in the configuration of the materials including the sampler type but the moment I add my ash layer T_Burnt_Forest_floor_uhxnacwn_8K_D and start painting with it, it causes the entire cell to permanently remove its texture as shown here:

I have moved the layer order and it didn’t change anything. Here’s how it looks like

As you can see, I’m not doing much with the texture layers right now, it’s as basic as it gets

What do you guys think? Running out of memory? It says Mem: 3,638.75mb

Edit: Also replacing it with other textures and their normal still causes the same issue.