I am able to edit the attributes of your service. However, it looks like you've disabled geometry edits, if that's what you're looking for.
You've also found a bug in explorer Online. It gives the impression that you can edit the geometry of features, and the display will reflect it, but the edit is actually not persisted in the feature service.
Bottom line, if you want to edit the geometry in this feature service, you need to enable it. Choose the option to "Add, update, and delete features"
Thanks,
Mike