diff --git a/12.temporary_ins/65.geometrical-optics/50.simple-elements/30.thin-lens/20.overview/cheatsheet.es.md b/12.temporary_ins/65.geometrical-optics/50.simple-elements/30.thin-lens/20.overview/cheatsheet.es.md
index 3d2f505fd..4f3f81580 100644
--- a/12.temporary_ins/65.geometrical-optics/50.simple-elements/30.thin-lens/20.overview/cheatsheet.es.md
+++ b/12.temporary_ins/65.geometrical-optics/50.simple-elements/30.thin-lens/20.overview/cheatsheet.es.md
@@ -5,7 +5,7 @@ published: true
 routable: true
 visible: false
 lessons:
-   - slug:simple-optical-elements
+   - slug: simple-optical-elements
      order: 3
 ---