Starting with Revit 2024, Autodesk has changed the way that they handle materials and the way they are stored, which has adversely affected the way Enscape behaves when it attempts to render them.
The base Revit material library is now called Textures.
Please add the folders below to the rendering location in the Revit rendering folder, restart Revit and Enscape, and test this again. There are other similar folders in the "Textures" directory that might need the same adjustment.
C:\Autodesk Shared\Materials\Textures\1\Mats
C:\Program Files\Common Files\Autodesk Shared\Materials\Textures\1\Mats
To complete this process, please open a project in Revit, click on "File" -> "Options" -> "Rendering" tab -> green "+" -> select the "..."-button in the new list item on the right -> go into the folder and click "Open" button. Repeat for all corresponding folders.