Safari browser contact form 7 Failed to send your message. Please try later or c

When using Safari on a Mac when you try submitting a contact form it displays the following error message with an orange border “contact form 7 Failed to send your message. Please try later or contact the administrator by another method.”

It works fine on Chrome, Firefox and Edge so not sure why it is having issues just in Safari

The page I need help with: [log in to see the link]