I was able to fix it by lowering my streaming pool size:
in the cmd run the command r.Streaming.PoolSize 1000000.
1000000 is what worked for me, you may need to change it.
The error suggests a null pointer access issue related to material parameter collections. To fix it, ensure your material parameters are properly initialized and check for any null references. Try rebuilding the project after clearing the binaries, intermediate, saved, and DDC folders. Also, verify that your project is compatible with your Unreal Engine version, and ensure your GPU drivers are up to date. If the problem persists, debug around the material parameter collections to isolate the issue, or create a new project and migrate your assets to rule out corruption.