I deactivated it via css
#top input[type=”checkbox”] {
display: none !important;
}
Disable Theme and disable plugins did not lead to success.
I do not know why, but after deleting these lines the form works again.
<p>OVBB-Newsletter<br />
[radio OVBB-Newsletter default:1 “Ja, ich möchte gerne den OVBB-Newsletter abonnieren, falls ich nicht bereits in der Empfängerliste erfasst bin” “Nein danke”]</p>
