Contact form 7, Loading problem

Hi,

I’ve got some problems with contact form 7. When i press the send button of my form the loading icon stuck. I’m not getting a thank-you message. I received the e-mails and the forms are coming in Contact Form DB.

When i use gravity forms i’m not having any problems. I tried to disable all the other plugins, but no success.

Inspecting tool gives this error:
2/wp-json/contact-form-7/v1/contact-forms/26522/feedback Failed to load resource: the server responded with a status of 500 ()
(index):1 XMLHttpRequest cannot load https://www.socialmediamonteur.nl/wp-json/contact-form-7/v1/contact-forms/26522/feedback. No ‘Access-Control-Allow-Origin’ header is present on the requested resource. Origin ‘https://www.socialmediamonteur.nl’ is therefore not allowed access. The response had HTTP status code 500.

Can you help?

Thanks in advance.

Robin Nieuwhof

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