09/20/2018 at 9:17 am
#472948
Keymaster
@ Katharina
Did you by chance copy/paste the shortcode from the web page into the WP Post editor? If you did, I recommend deleting it all and manually typing it instead. When you copy/paste, you also copy/paste the underlying HTML from the source web page. This HTML will break the WP shortcode parser.
Hope that helps, let me know.