Error when sending a message

Hi

Im trying your contact form and I’ve added a pdf file to upload. But it says there’s an error and it couldnt send the message. I then tried to remove the file-upload part and it still doesnt work.

I used this code: [file your-file filetypes:pdf|txt limit:2mb] from this guide: https://contactform7.com/file-uploading-and-attachment/ (it cant send a message even when I delete this).

This is the site I’m editing: https://test1234.dk/upload-dokumenter/

What could be the issue?

Best regards
Sara