404 page is not accessible

[Manvel]

Reproduction steps

1. Navigate to https://cmints.io/en/documentation/pages/404
2. observe

Observed behavior

The page doesn't exist

Expected behavior

The page exists and shows content of https://github.com/cmints/website/blob/master/pages/documentation/pages/404.md

[Manvel]

The problem seem to be related to the subfolder named pages.