Hooks not working: 404 response when requesting /projectname/hooks/id

Created by: anapq

I'd like to create a web-hook in gitlab 2.7.0. After adding a hook the test-button doesn't have any effect and I get a 404 when clicking on the link (requesting /projectname/hooks/id). The log is saying: ActionController::RoutingError (No route matches [GET] "/my_project/hooks/3"): ...