We have upgraded our Sitecore from 7 to 9. Not loading the Css and Js files
Create a patch file to have Sitecore ignore the url you're using in your bundle. Without that, Sitecore will try to serve something up itself. Here is an example of the patch file you need (you can strip out the rest):
https://www.sitecorefundamentals.com/using-sitecore-to-manage-your-bundled-assets