How can I change the language?

You can do this via the settings for the account. Click on the icon with the person on the upper right-hand edge of the screen and select "Settings". This opens the Account Portal in a new window. You may be prompted to enter your login data again. Please enter this data and you will then be taken to the "Profile" tab of the Account Portal. This is where you will find the "Language" selection box in the "Profile information" section. Select your target language and save the change. Then close the window and refresh (F5) the browser window that contains the application.