Umbraco 11 umbraco-backoffice-css not loading

Questions
1

Hi there,

When I open Umbraco forms on pre-prod styles are not displayed and I got an error that umbraco-backoffice-css.css.va4b5e1ce98dd4891686476705097f get **

System.IO.FileNotFoundException: No such file exists
/portfolio-assets/bootstrap.css (mapped from
/portfolio-assets/bootstrap.css) File name:
‘/portfolio-assets/bootstrap.css’ error

**

enter image description here
enter image description here687×705 29.5 KB

This is a companion discussion topic for the original entry at https://our.umbraco.com/forum/111608-umbraco-11-umbraco-backoffice-css-not-loading