After Form Message is Not Appearing

Hi,

I have an after form message (Advanced > After form message) set on my form, but it’s not appearing on the page with the form.

Here’s a screen to show what I want:

https://i.imgur.com/qRJqL6y.png

Any idea what I can do to get this to work?

Thanks..

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