Can you please share the screenshot of the page, where you are using this button,
If you are using a button that leads you to the registrations page, then you have to put the button itself in the listview and then use it to go to the registrations page,
Hope it helps!
in the event onclick dropdown, rather than choosing Show a Page, choose the Create object option.
You can select create object from dropdown and choose respective entity where you want to store your details and then choose your page.
Hope it helps…!