Checkbox not working

[Carlo]

Hi all.
I am using this software since June so probably it's my fault but am experiencing some difficulties with the forms.
I want to put a checkbox so that accepting the Privacy Policy them it is allowed to send out the form.
I used the conditions, disabled the 'Send' button but even though the user leave the checkbox unchecked, the message is sent out without blocking the user.
Any suggestions ? Please ! Thank you very much.

[Pablo]

What exactly did you do?
What are your settings?

See also:

[Carlo]

Hi
Thank you for answering.
I'll post the demo file later.
Thanks