Chronoform submit adding backend port to url

Using chronoforms 6 I can't get forms to submit on my production server because after clicking submit it's adding the backend port to the url.
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How do I get it to not add that 32773 to the end of my domain name?
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So it's doing...
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form action="https://myurl.com:32773/index.php?option=com_chronoforms6&chronoform=formt&event=submit"

Hi Joe,
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I have no idea - presumably a server setting somewhere. You can hard code the form Action URL to get round it.
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Bob