I am having the same issue.
1)There are two save buttons. One above the “How many events…How many attendees” and one below. The save below shows success but doesnt update the general settings. The top save button (which I assume is the current tab save) gives me an error.
2) the Capcha isn’t working either. i am trying to turn it off but I can’t save the settings. The Capcha has the fill in spot but no Capcha is shown.