Fix ml instead confusing module

docs.it4i/software/lmod.md

@@ -263,7 +263,7 @@ $ which gcc
 
 ## Resetting by Unloading All Modules
 
-To reset your environment back to a clean state, you can use ml purge:
+To reset your environment back to a clean state, you can use ml purge or ml purge --force:
 
 ```bash
 $ ml