JOSM - Mapnik layer randomly stops loading

I’ve had a weird issue recently, and I don’t know if it’s something wrong on my end or OSM’s, or if it’s just a weird bug in JOSM, but after a while of using it, the Mapnik layer will stop loading anything when I zoom in/out or pan in any direction. Even when I delete and re-add the layer (which sometimes fixes slow loading issues like this), it stays the same. The only thing that fixes it is restarting JOSM, which makes it work fine again until it randomly stops working again. When it happens, I can connect to just fine, and pinging both it and the tile server in the command prompt both work, but it still won’t load in JOSM.

All the other layers work fine, including the Bing satellite view and the black and white Mapnik layer.

Has anyone else had an issue like this, and is there anything I can do to fix it? Restarting works, like I said, but it’s annoying to do every time.