File l3backend-pdftex.def Not Found, even after installing l3backend

I’ve seen the previous threads on this error such as this thread and this and carried out the instructions here.

So that being said, I’ve installed l3backend through MikTex Console and I still receive this error. Here’s a screenshot of my MikTeX console.

I’m getting the error on the simplest possible examples. Here is what the setup wizard puts out — it gives me an error.

documentclass[12pt,a4paper]{report}
usepackage[utf8]{inputenc}
usepackage{amsmath}
usepackage{amsfonts}
usepackage{amssymb}
begin{document}
This... is a test...
end{document}

Screenshot of TexMaker follows. I’ve reinstalled MikTex, reinstalled the l3backend package and restarted my computer numerous times. Not sure what to do next. Any help is appreciated. Thanks.