Try uninstalling the application first.
When you use Xcode to deploy to a device (or simulator), resources are added, not deleted.
Most likely, now you have three html files. One in the folder de, one in the folder enand one in the root folder.
And if he is there, iOS prefers one in the root folder.
As a rule: when you delete (or in this case move them) resources from your project, you must remove the application from the device or simulator.