We are constantly improving our app and regularly release updates. To make sure that apps continue to work as usual, you should always keep your operating system up to date. You can also check in the Android and iOS apps whether you have installed the latest version of the app or whether an update is available in the app store. If the app does not work despite having the latest version, we recommend closing the app again and restarting it. Restarting the smartphone can also help to restore the function.