Calculate button is not displayed

Hi there, I am working on a website at the moment for a company that need a calculator.

I am trying to show them the free version of the plugin before they buy it, however after filling in all of the required fields and adding the calculation…there is no button to press that says ‘Calculate’.

I cannot find any instructions that explain how to use the calculate button the same as in the Wow-Company demos.

Can you help please? Can you tell me how to add the button that says calculate?

Thank you.