Hiya, @adamdjbrett 
Thanks for sharing that information, and welcome to the Netlify Forums! I am sorry you are having trouble getting your forms to work.
This Support Guide is the first port of call to debug any forms issues. Please start here and work through these resources!
If you are still having problems after following the suggestions in those guides, please also share the name of your form as it exists in the UI and a link to the live form. The site you shared above throws a site not found error, so I cannot see the form or complete a test submission to recreate your error.