Translated contact form not working

My English contact form works perfectly, but when I try to submit a message through my translated contact form (German) I get an orange-framed error message (“Beim Versuch, deine Nachricht zu senden, ist ein Fehler aufgetreten. Bitte versuche es sp?ter nochmal”)

The German contact form is exactly like the English contact form, the only difference is the language, what could be causing this?

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