Folder not accessible

Hi*
we have a problem with a folder on the server. I have created a new folder in the WordPress folder. But I can’t reach the files that are in the folder – I’m always redirected to the index page. The folder is located at the level of the wp-content folder. Do I have to make settings somewhere to use the new folder? Or is it not possible to create your own folders in the structure?

Thanks for your help!

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