[Plugin: Fast Secure Contact Form] Optional Parameters Problem

Hi

I am using the latest versions of WP and FSCF and I’m trying to use optional parameters in the shortcode:
[si-contact-form form=’9′ hidden=’PropertyID=3629675,PropertyName=LargeHouse’]
but when the email comes through they both display as
Form Page
https://mysite.com/path-to-my-form-page/

I have tried defining the hidden fields in the form setup with values as “x” but then it just displays
PropertyID
x
PropertyName
x
followed by the Form Page details as above

Any suggestions, please?

https://www.ads-software.com/extend/plugins/si-contact-form/