I did some fire simulations in blender about a week ago. I encountered the same problem in all of them, the fire was not loading in the render view, all I get are some huge black pixels. It works well in the object view.
this is what it looks like in the render view.
I looked it up on Youtube and other forums, but I didn't find anyone facing this same problem. I am using Blender 3.0(beta), but even when I opened the same project in older versions of blender it showed the same effects.