Bug in Bookings: One-Time Password

I found a strange bug in Bookings. When I enabled the option "Require a one-time password to create bookings" under the menu "Business page access control" and the language is set to English or Spanish, prior to being able to make the booking a modal will open which asks for a validation code, just as excepted. However, when I switch the language to German, an error is shown which states that the booking is not possible. In both cases, the e-mail with the validation code is sent.