Page reloaded when "back arrow" clicked

9.2 HCM PUM Image 54, Tools 8.61.08

I created a very simple custom page to capture an employee election and save their submission to a small custom table.

After they submit and the selection is saved, I display the page (now disabled), with a pop-up message.

After clicking out of the message, and clicking this 'back' arrow (where it will return them to the landing page), the page will actually reload and display again, with the popup message. Once they click through that, and click the 'back' arrow, they go to the landing page.

How do I stop this reload of the page? It's not a deal-breaker; just annoying.