CF7 Event-Tracking Google Analytics

I really dont get it. I had this problem also with a similar site.
Notice: I didn′t build this site.

Problem:
I`m trying to track submitted contact forms in google analytics with contact form 7. I tried the following:

1. I placed the code

on_sent_ok: “ga(‘send’, ‘event’, ‘Contact Form’, ‘submit’);”

in the additional settings. Does not work. This method is supported until the end of 2017. The new method is “DOM events”, so…

2. …I tried it with DOM events. I placed the code

<script>
document.addEventListener( ‘wpcf7mailsent’, function( event ) {
ga(‘send’, ‘event’, ‘Contact Form’, ‘submit’);
}, false );
</script>
in the head of the template. Also, does not work.

3. I also tried a WordPress plugin “Contact Form 7 Google Analytics” and this doesn′t work either. No matter which way I tried: The site doesn′t execute the line:

ga(‘send’, ‘event’, ‘Contact Form’, ‘submit’);

No event appears in the live view of google analytics. I had this problem a few months ago (WordPress and Google Analytics Events) but this is a new site and i think its the same problem. There must be reason? I dont have this problem with other wordpress-sites.

Maybe important: After submitting a form there is no “thank you message”. Nothing happens an the url changes to https://page.xyz/kontakt/#wpcf7-f4-p18-o1 I think this is not normal?

I am really happy about any help. Thank you!

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